The Australian Granny Flat Handbook

About this handbook

This handbook helps Australian property owners investigate a granny flat or another small dwelling before committing substantial money. It explains how to check the land, identify the approval pathway, compare complete project costs, investigate a builder and prepare for a contract review. It also considers family accommodation, rental use and importing a dwelling. Use it to organise evidence and prepare questions for the people assessing your actual project. A favourable answer in a checklist is a reason to continue investigating. It is not a planning approval, a building certificate or a guarantee that the project will be affordable. The book is written primarily for homeowners and prospective buyers. Family members contributing to a project can also use it, provided the landowner is involved and the necessary authority to act is established. It is not a construction manual, a contract template or a substitute for professional services.

Important information

This publication provides general educational information. It does not provide advice tailored to your land, design, finances or circumstances. It is not legal, tax, investment, credit, valuation, planning, engineering or building certification advice. Before a consequential decision, obtain current information and advice appropriate to that decision. Depending on the issue, consult the responsible planning authority, a building surveyor or certifier, a registered surveyor, an engineer, a suitably licensed builder, a construction or property lawyer, a registered tax agent, or an appropriately authorised finance professional. Regulatory information is a dated summary. Requirements can depend on the property, proposed use, contract type, application date and transitional provisions. Check the current official source and the instrument applying to your project before relying on a figure or rule, even if this edition is recent. Links and source dates appear in the reference directory. Guidance pages help explain the rules; the applicable legislation, planning instruments and approval conditions determine the legal position. No approval, saving, rental income, capital gain or successful outcome is promised. Worked financial examples are fictional teaching examples prepared for this edition. Their inputs are not market evidence, quotations or recommended allowances. They illustrate calculations only. Nothing in this handbook excludes, restricts or modifies any consumer guarantee, right or remedy that cannot lawfully be excluded, restricted or modified under the Australian Consumer Law or other applicable law. The description of this book as general information does not remove those rights. See the ACCC consumer guarantees guidance [S01].

How this website is funded

Tiny Home Guru Oz provides this information free of charge. We may receive payment from builders for referrals. Contact details and questionnaire answers are reviewed by us first and shared with one builder only when you explicitly opt in. Reading this guide does not require submitting your details.

Copyright and permitted use

© 2026 Tiny Home Guru Oz. Rights reserved to the extent protected by law. You may save and print this handbook for your personal use and complete its exercises for your own project. You may share the relevant completed project records with your professional advisers. Redistribution or resale of the publication requires the publisher's written permission, except where permitted by law. Third- party sources retain their own rights. For publication enquiries, use the contact details on this website. When reporting a possible error, identify the edition, section and official source concerned. Do not rely on this edition as a promise of future updates.

How to use the book

Start with the land and intended use before becoming attached to a particular building. You can read the chapters in order or follow the route that matches your next decision.

Your first actions

Write down who will live in the dwelling, how it will be used and what you can afford. Gather the title documents and the property's lot and plan details. Open the official planning information for the address. Sketch a possible location and access route without treating the sketch as a design. Then use the enquiry in Chapter 5 to ask the responsible authority what applies.

Create a project folder with sections for land and approvals, design and services, quotes and budget, builder and contract, inspections and payments, and completion. Save the source, date and version of each document. Give drawings clear revision names so a quote based on an older plan does not get mistaken for a quote on the current one.

Reading sources and numbers

Reference codes such as [S01] identify entries in the directory at the end. Each entry provides the organisation, document or page title, the source date where available, a review date and a clickable link. Use the current guidance or instrument linked there when you revisit a decision. If a link moves, search the named organisation's own website for the exact title.

Numerical legal thresholds are snapshots, not instructions to design or pay to the maximum. Their conditions matter. Numbers in the worked examples are labelled assumptions and have shown arithmetic. There are no national construction-price, savings or rental-return benchmarks in this edition.

Advice received by phone, a map screenshot and an informal email can be useful records, but none automatically authorises construction. Save any formal approval separately, together with its endorsed plans, conditions and expiry information.

1 Check the land and the purpose

Buying a building and finding somewhere lawful to put it are different decisions. Start by establishing whether the proposed use is worth investigating on this particular property. Early checks can reveal a restriction, a service problem or a funding gap while you still have room to change the proposal.

Establish authority over the property

Obtain a current title search, the relevant plan and the instruments affecting the title. Ask a property lawyer or conveyancer to explain easements, covenants, restrictions, lease conditions and the authority needed to enter a building contract. A clear-looking backyard does not tell you what rights another party holds over it.

For strata, community title or other shared ownership, ask what consents are necessary and whether common property is involved. For leasehold land, check the permitted use and any lease-change process. If the land belongs to a trust, company or estate, confirm who can authorise and sign the work. These are property-specific legal questions, not matters that a builder's brochure can settle.

If you are contributing money to someone else's land, settle your rights before transferring it. Family trust does not answer what happens on sale, separation or death. Chapter 8 explains the questions to take to independent advisers.

Ask the lender whether the proposed works, additional dwelling and intended use require consent or alter the loan conditions. Record the answer. An approval from a planning authority does not establish a lender's agreement.

Check the planning position

Find the exact parcel in the official planning system. Record the zone, relevant overlays and the proposed land-use category. Ask whether the proposal is permitted, which pathway applies and which controls need assessment. A residential zone label alone does not answer those questions.

State and local instruments do not form a universal hierarchy in which a council can always impose a stricter rule. The legislation determines how the instruments interact. A state pathway may constrain local controls; a local rule may matter in a different pathway. Ask for the actual provisions, rather than choosing whichever website sounds most confident. The NSW Housing SEPP is an example of a state instrument governing a secondary-dwelling pathway [S04].

An overlay can add a requirement, change a pathway or restrict development. Do not assume its presence means automatic refusal, or that its absence establishes a safe or suitable site. The responsible authority and relevant specialist must interpret the actual constraint.

Test the physical site

Start with reliable dimensions, then commission the survey and investigations required for the proposal. A title plan or online map is not a substitute for setting out boundaries and levels on the ground. Ask the surveyor what the work will establish and what remains outside its scope.

Consider the space left for the existing home as well as the new one. Access, outdoor space, drainage, privacy and maintenance all need to work after construction. A building that fits geometrically may still create an uncomfortable arrangement or fail an applicable control.

Walk the intended delivery route. Record narrow sections, slopes, trees, overhead lines, turning areas and any neighbour's land that would be needed. For a factory-built unit, ask the transport and lifting contractors to assess access before ordering. Do not rely on your own measurements to approve a crane lift or road movement.

Ground conditions need investigation. Ask about the required soil report, footing design, retaining works and drainage. Keep unresolved site conditions visible in the budget. A general allowance does not establish what the contractor will charge if a particular condition is found.

Find the service constraints

Identify the water, sewer and electricity providers and who assesses work near their assets. In some places a council supplies or regulates a service; in others a separate utility is responsible. Ask the planning authority who to contact and obtain the provider's own instructions.

Obtain available asset plans and confirm whether a physical service-location survey is needed. A diagram may be approximate or incomplete. It does not authorise excavation or building near an asset. Ask whether protection, relocation, access rights or an additional approval is necessary.

For an unsewered property, have an appropriately qualified professional assess wastewater capacity and disposal requirements. Ask the authority whether the existing system can serve the proposal and what approval or upgrade is required. Do not assume an existing system has spare capacity because it currently works.

Ask an electrician and the network provider about supply capacity and any upgrade. Ask the plumber about water pressure, connection arrangements and lawful charging if the dwelling will be rented. Separate meters, bins or mailboxes are not a universal legal test for whether a building is a secondary dwelling.

Write a purpose statement

Describe who will use the building, for what purpose and for how long. Include whether you intend ordinary rental, short stays, family accommodation, a paid lifetime occupancy arrangement or your own home. A change in intended use can change the enquiries you need to make.

Then write the spending limit and how you will fund it. Include the effect on the existing household during construction. If the family must relocate temporarily, lose a driveway or delay rental income, record that consequence rather than leaving it outside the budget.

At this stage, classify each issue as answered, requiring advice or preventing the next commitment. Do not add the answers into a score. One unresolved title restriction or unaffordable service upgrade can matter more than several favourable answers.

2 Choose a construction approach

The way a dwelling is made does not by itself determine the permission needed to use it. Compare construction methods only after defining the intended use and identifying the likely planning and building categories.

Building on the site

A site-built project allows the design and construction sequence to respond to the block. The contract should explain site preparation, access, footings, services and completion. Establish who coordinates approvals and specialist reports and which costs remain yours.

Ask how the work will affect the existing home. Access for trades, security, temporary fencing, noise, dust and service interruptions should be discussed before work starts. Put agreed arrangements in the contract documents where appropriate.

The legal classification and applicable technical requirements still need professional assessment. Do not infer that any small residential structure is approved merely because it resembles another granny flat.

Factory construction and modular delivery

A transportable or modular building can be designed and manufactured to meet Australian requirements. Obtain the design documentation and evidence supporting that claim. Product or system certification can be useful within its scope, but it does not grant permission to install and occupy the unit on any property. CodeMark certificates, for example, have a defined scope and conditions [S02].

Have the relevant surveyor or certifier and engineer identify what evidence they need before fabrication begins. Ask how concealed factory work will be inspected or documented, what site inputs are required and who takes responsibility for the interfaces between the factory unit, footings and services.

Split the practical responsibilities clearly: factory manufacture, transport, lifting, foundation construction, joining modules, weatherproofing, services and final completion. An omitted interface can become a disputed extra even when each contractor has delivered its own package.

Confirm ownership and insurance while the unit is at the factory, in storage, in transit and on the site. Ask what happens if the supplier fails before delivery. A factory inspection and an insurance certificate answer different questions.

Tiny homes on wheels

A trailer registration or the presence of wheels does not prove that someone may live in a unit on a particular property. Planning, building, caravan or camping, road, wastewater and tenancy rules may all be relevant. Describe the proposed placement, connections, duration and occupants when seeking advice.

Ask the responsible authority to identify the actual occupation rules, any permit or exemption conditions and the effect of renting it. Do not treat temporary placement as permission for indefinite residential use. Obtain a fresh answer if your use changes.

Road compliance is a separate enquiry. The Commonwealth's Vehicle Standards Bulletin 1 provides guidance for trailers up to 4.5 tonnes aggregate trailer mass; the linked edition is Revision 6 dated 19 August 2026. Applicable vehicle standards, registration and movement requirements still need checking with the relevant authorities and transport operator [S03]. Do not use this handbook to determine towing capacity, dimensions or route permissions.

Before ordering, obtain written finance and insurance terms for the actual unit and use. Ask whether the lender accepts it as security, when funds become available, what the policy covers and whether rental,

storage, transport and removal are included. Availability is a commercial question that must be checked with the provider.

Containers and kits

A container conversion and a kit are purchasing or construction methods. Ask how the finished building and intended occupation will be classified. A container's original transport purpose does not establish its suitability as a residence.

For a kit, define what is supplied, what must be built and who will carry out and supervise that work. Include engineering, weatherproofing, services and certification evidence in the enquiry. A materials list is not a complete construction contract.

If considering owner-building, contact the local building regulator before buying. Ask about permits, eligibility, licensed trades, supervision, safety responsibilities, insurance and obligations on later sale. The rules are jurisdiction-specific. Engaging some contractors does not by itself remove the responsibilities you take on as an owner-builder. Use the regulator directory [S30].

Importing

Importing adds customs, tax, biosecurity, shipping and overseas enforcement questions to the site and building checks. Chapter 12 sets out the sequence. There is no assumed saving: compare a complete import budget with an equivalent domestic scope.

Compare the options against your needs

Choose the option whose requirements and trade-offs you understand. The cheapest advertised object may not produce the lowest complete project cost, but a higher price is not evidence of better suitability either.

3 Understand approvals and responsibilities

Planning addresses the proposed use and development of the land. Building regulation addresses the construction and relevant technical requirements. Check both. Depending on the location and proposal, a planning exemption, combined certificate or separate applications may apply. An exemption has conditions; it is not permission to ignore other requirements [S04, S05].

Identify the applicable pathway

Ask the responsible authority whether your proposal is exempt or accepted, eligible for a code-based or streamlined assessment, or requires another development assessment. These are explanatory descriptions, not a universal national classification system. Names, decision-makers, notification and review rights vary.

If a design fails a streamlined standard, ask whether another lawful pathway or a revised design is possible. Do not assume the development is prohibited, that a variation is available, or that there is no review mechanism. Obtain advice about the specific provision.

When a supplier says approval is unnecessary, ask which approval, under which instrument and on what facts. Keep the written answer with the source. If the answer concerns only planning, separately establish the building, plumbing, service and occupation requirements.

Understand the building code

The National Construction Code sets technical requirements and takes legal effect through state and territory arrangements. Applicable editions, variations and transitional rules must be checked for the project. A newer national edition does not automatically establish the edition that your authority will apply [S31].

Ask the building professional to identify the classification, applicable code edition and compliance approach. Site inputs can include wind, climate, ground, flood and bushfire conditions. Energy efficiency, condensation management and accessibility requirements also need assessment under the applicable rules.

A Deemed-to-Satisfy approach follows specified provisions. A Performance Solution demonstrates that the relevant performance requirements are satisfied through an appropriate assessment. Ask who prepares the evidence, who assesses it and whether the quoted fee covers that work. Certification should be evaluated against its actual scope [S02, S31].

Know who is responsible

The planner interprets the planning pathway and relevant controls. The designer coordinates the proposed layout and documentation within the agreed scope. Surveyors and engineers provide specialist measurements or designs. A building surveyor or certifier carries out statutory functions within the jurisdiction's system. The builder performs the contracted work and has obligations under the applicable law and contract.

Obtain a written responsibility list rather than assuming each person will fill gaps left by someone else. In particular, assign responsibility for lodging applications, obtaining service permissions, booking inspections, responding to information requests and obtaining final documents.

Appointment rules matter. In Victoria, a domestic builder must not appoint a private building surveyor on the owner's behalf. Recommending a surveyor is different from appointing one. Follow the current appointment process rather than treating independent appointment as merely a preference [S06]. Elsewhere, confirm the local process with the regulator [S30].

Statutory inspections are not a promise that every finish or contractual detail has been independently checked. If you engage a separate inspector, agree the inspection scope, timing, reporting and access with them and the builder.

Allow for the whole approval process

Ask for a list of required documents, fees, referrals and likely dependencies. A quoted assessment period may exclude the time spent preparing drawings, obtaining specialist reports or answering requests for information. Ask whether a stated duration means calendar days or business days and what starts the clock.

Check approval conditions before treating the building contract price as complete. Conditions can require additional design, works or evidence. Confirm when each condition must be satisfied and who will pay for it.

Keep formal approvals, endorsed drawings and subsequent amendments together. Do not let a drawing change at the factory or on site without checking whether it needs approval and whether it changes the contract. Chapter 10 covers recording variations.

4 Find your state or territory starting point

These profiles identify useful official sources and selected verified rules. They are not a complete statement of each planning scheme. All numerical snapshots in this chapter were checked on 8 September 2026; verify the operative instrument again for your application. The reference directory includes direct links and source dates.

Read your profile alongside the site enquiry in Chapter 5. Do not transplant a floor-area definition, parking rule or permission from another jurisdiction. These profiles concern the named dwelling categories; they do not establish the occupation rules for a tiny home on wheels.

New South Wales

The NSW department describes a secondary dwelling as a self-contained dwelling within, attached to or separate from another dwelling on the same site. The Housing SEPP provides consent and complying- development pathways. The departmental guidance says the complying pathway ordinarily requires a lot of at least 450 m², with an exception for a secondary dwelling entirely within an existing dwelling house. A smaller lot may still warrant enquiry about a development application [S04].

Check the secondary dwelling's own floor-area control separately from the combined floor-area calculation for the development. The latter can include the main dwelling and attached structures. Ask the certifier to identify the applicable clauses and show both calculations on the plans. Do not interpret a combined-development test as the size limit for the flat alone [S04].

Check existing parking conditions and any parking removed by the proposal. The secondary-dwelling pathway does not grant separate title. For rural land, identify the relevant local environmental plan provisions rather than assuming the residential pathway applies [S04].

Check now: NSW secondary-dwelling guidance and the current Housing SEPP [S04]. Ask about permissibility, area measurements, complying-development exclusions, existing consent conditions and contributions.

Victoria

A small second dwelling has a gross floor area of 60 m² or less on the same lot as an existing dwelling. Planning Victoria states that a planning permit is not required in many cases, but a building permit is required. Its guidance also states that a small second home must not connect to reticulated natural gas and does not require a car parking space [S05].

The applicant material uses an external-wall gross-floor-area measure that includes roofed areas. Have the designer calculate it using the actual definition. The residential-zone exemption described in the brochure uses lots of 300 m² or more; other conditions and overlays still need checking. Some overlays have conditional exemptions, so their presence does not settle the pathway by itself [S05].

Family and unrelated occupants can live in a small second home, subject to applicable rental requirements. Existing lawful dependent-person units remain lawful despite the stated 28 March 2027 transitional expiry; a changed use needs separate checking [S05].

Check now: Planning Victoria's current page, applicant guide and relevant planning scheme [S05]. Ask about the specific exemption, floor-area calculation, siting requirements and any existing unit's lawful use.

Queensland

Queensland's state planning guidance allows a secondary dwelling to be rented to someone outside the main household. The announced review of the occupancy change was not an automatic expiry of that change. Existing approvals, lawful use and relevant safety and tenancy requirements still need checking [S07].

The local planning scheme is central to determining the secondary-dwelling controls and assessment pathway. Ask for the current definition, size control and relevant accepted-development requirements or application route. Do not use a single floor-area figure as a rule for the whole state [S07].

A separate mailbox, meter or driveway is not, by itself, a universal Queensland test for dual occupancy. Ask how the actual design is assessed under the applicable scheme. Separately check tenancy and utility-charging rules before setting up a rental arrangement.

Check now: Queensland planning guidance, the council's operative scheme and the Residential Tenancies Authority [S07, S32]. Obtain the scheme version and the provisions applying to your address.

Western Australia

The R-Codes collection is the official starting point for ancillary dwellings. The reforms removed the former 350 m² minimum lot requirement, and the current collection addresses ancillary dwellings associated with grouped or multiple dwellings and strata arrangements. It is therefore unsafe to assume every eligible lot must contain only a single house [S08].

The ordinary deemed-to-comply ancillary-dwelling floor-area criterion is 70 m² in the linked material. Confirm the relevant R-Code part, area definition and current local framework. A proposal must meet the applicable conditions to rely on a planning exemption; ask separately about the building permit [S08].

Do not assume additional parking is never required. Check the parking provisions and the existing approved arrangement. Strata consent and title restrictions remain separate questions from planning eligibility.

Check now: The WA Residential Design Codes collection and the local planning scheme [S08]. Ask which part applies and whether the proposal satisfies every relevant exemption condition.

South Australia

The Planning and Design Code uses ancillary accommodation. The official November 2024 amendment update confirms that the maximum floor-area criterion increased from 60 m² to 70 m² and the definition was changed. Use the adopted Code for the detailed definition and the assessment tables applying to the property [S09].

Ask how the proposed kitchen, bathroom, servicing, bedrooms and relationship to the main dwelling fit the current category. Do not infer the complete approval pathway from the term granny flat. The relevant zone, overlays and proposal must be considered in the Code.

For a rental proposal, establish the planning and occupation position and then check the applicable tenancy requirements. A planning category does not itself establish that a particular tenancy arrangement is ready to start.

Check now: PlanSA's online Planning and Design Code and the official amendment record [S09]. Request the definition, assessment pathway, floor-area calculation, siting controls and building-consent requirements for the proposal.

Tasmania

Tasmanian secondary-residence enquiries should begin with the State Planning Provisions and the property's Local Provisions Schedule. Confirm the operative text and any relevant building-work category with the responsible authority [S10].

The Planning Commission's record for draft amendment AM-SPP-01-2026 describes proposed changes to secondary residences. A consultation or assessment page does not establish that an amendment has commenced. Obtain the operative scheme and commencement information before designing to a figure discussed in a proposal [S10].

Ask how floor area is measured, whether and how services and access must be shared, what the applicable parking provisions require and how the zone and codes affect assessment. Separate meter

arrangements should be checked under the actual provisions rather than treated as an automatic national or statewide test.

Check now: The Commission's current amendment record and the operative planning scheme [S10]. Ask the council to identify the version and provisions applying on the intended application date, including any transitional arrangements.

Australian Capital Territory

Use the ACT planning authority and the current Territory Plan, rather than assuming a local council pathway. Check the Crown lease, land-use provisions, technical requirements and any applicable exemption process together [S11].

Ask for the current secondary-residence definition, permissible floor area, block requirements, access, parking, open space and assessment pathway. Older FAQs are useful background, but should not settle a current design. Have the authority or adviser identify the operative instrument and provisions.

Renting a secondary dwelling can create a land-tax liability even when the owner lives in the principal home. ACT Revenue explains the apportionment and notification requirements. Obtain advice on the actual use and ask separately about rates; do not budget on an assumption that both remain unchanged [S12].

Check now: Current ACT planning material and ACT Revenue's land-tax guidance [S11, S12]. Include the lease and proposed rental use in the enquiry.

Northern Territory

The current NT scheme uses the term dwelling-independent. Clause 5.4.13 of the linked Development Requirements sets ordinary floor-area limits of 100 m² in zones H, A, RL and R, and 75 m² in other zones. It also contains additional conditions and limited discretion concerning area. Read the whole clause with the applicable zone and overlays [S13].

The clause addresses the number of dwellings and arrangements including shared services and access. Do not treat the size figure as a standalone entitlement. Ask the NT planning authority about the proposal's assessment category and any special-use provisions. Separately establish the applicable building-control requirements for the location.

Check now: The NT Planning Scheme collection and current Part 5, especially clause 5.4.13 [S13]. Ask for the zone-specific pathway and any geographic or proposal-specific requirements.

Before choosing a design

Have your adviser confirm the relevant dwelling definition, how its area is measured, the assessment pathway and the controls that constrain your proposal. Keep the answer with the drawing revision it concerns. A plan advertised as suitable for a state has not necessarily been assessed for your lot.

Do not assume a secondary-dwelling approval creates a right to separate title, additional ancillary units or future subdivision. Those intentions need an explicit planning and title enquiry. If separate ownership is central to your plan, investigate that before selecting the ancillary-dwelling pathway.

5 Get an answer for your address

The purpose of this chapter is to turn general research into an organised property enquiry. You are seeking the applicable provisions and a clear account of what remains to be assessed, not an informal promise that the project will be approved.

Prepare the property record

Gather the street address, lot and plan details, title documents, approximate proposed location and a description of the intended use. Identify the main dwelling and any existing sheds, units or approvals. Make clear whether a structure is proposed, already on the site or being converted.

Use the official planning portal linked for your jurisdiction [S04 to S13]. Locate the parcel, check the selected layers and save the available property report or relevant extracts. Record the date, map layer names and any limitations shown by the system. A property report can help identify questions, but it may not show every constraint or private title restriction.

Ask the authority which current maps and instruments apply. If a local webpage and a state page disagree, provide both links and ask for a provision-based explanation. Neither a builder nor a council webpage is infallible. Resolve the discrepancy before relying on the answer.

Send a focused enquiry

The following wording is an enquiry aid. Adapt it to the property; it is not an application or a request for a guarantee.

Subject: Proposed secondary dwelling at my property

I am investigating a proposed small dwelling at [address], lot [number] on plan [number]. The existing use is [description]. The proposed dwelling would be [attached, detached, modular or other description] and used for [family accommodation, ordinary rental or other use]. I have attached a preliminary sketch and the property information I have gathered.

Could you please advise:

 What land-use category would this proposal be assessed under, and is that use permissible on the land?  Which planning pathway and current instruments apply? Please identify the relevant provisions and any transitional rules.  What floor-area definition, siting, open-space, parking and access controls should the designer check?  Which mapped or other constraints affect the proposal, and what investigations or specialist reports are needed?  What building, plumbing, wastewater, service-provider or other approvals should I enquire about separately?  Are contributions, infrastructure charges or other development-related charges potentially payable? Where is the current schedule, and what determines the amount and payment date?  Do existing approvals or conditions restrict the intended occupation or rental use?  Is a pre-application meeting or formal written advice available, what does it cost, and what legal status would the response have?

Please let me know what further information you need and which other authorities I should contact. I understand that preliminary advice does not replace the required formal approvals.

Record the response properly

For a call, record the date, officer's name, role and the facts you supplied. Send a short follow-up confirming your understanding and invite corrections. Keep the response with its attachments. Do not treat silence as agreement.

If the advice assumes a particular size or location, record that assumption on the sketch. A response to a detached family-use dwelling may not answer a later proposal for short-stay accommodation in a different position.

Separate the answer into what has been confirmed, what depends on a design and what needs another authority. Assign the unanswered questions to someone and identify which spending decision should wait. This avoids repeatedly asking different people a general question without resolving the specific issue.

Contact the service providers

Ask the water or wastewater authority about existing assets, connection capacity, building near assets and any separate approval. Ask the electricity provider or electrician about supply capacity and the proposed installation. If a unit needs delivery by road and lifting onto the site, obtain the relevant contractors' access assessment.

Request written scope and cost information when commissioning these services. Ask which investigations are included, how long a quotation remains valid and what further work could follow. There is no assumed fee or turnaround time in this handbook.

Decide what evidence is still needed

Your folder should now contain the available title and planning information, service records, a clearly described proposal and the advice obtained. It may also contain unresolved issues. That is a useful result if the issues are specific enough to investigate.

Before commissioning detailed drawings, agree with the designer what the next stage will establish and what happens if a major constraint prevents the proposal. Ask about the fee, ownership and permitted reuse of the drawings, and the cost of revisions. A limited initial engagement may be appropriate, but its value depends on its written scope.

6 Build the complete project budget

The contract price may cover only part of what you must pay. Build a budget around the completed, lawful use of the dwelling, including costs outside the building supplier's scope. Use written quotations where available and keep uncertainty visible.

Make every line explain itself

For each cost, record the scope, amount, GST treatment, source, date, expiry and who will pay it. Mark it as quoted, estimated, unknown or not applicable. If it is not applicable, record why. An unknown line is not zero.

Distinguish money already spent from money still required. Also distinguish a fixed quoted amount from an allowance that can change. A total containing estimates is an estimated total even if the addition is exact.

Before construction

Allow for the title and survey information, design work and specialist reports the proposal needs. Possible items include geotechnical investigation, engineering, energy assessment and reports dealing with relevant site constraints. Ask the designer and certifier for the actual list rather than buying every report mentioned in a generic guide.

Include planning and building fees, certifier or surveyor services, inspections and any professional contract review. Ask which fees cover amendments or further information requests. If approvals are being obtained by the builder, identify the scope and any excluded charges in writing.

Site works and access

Discuss clearing, demolition, lawful disposal, excavation, foundations, retaining, drainage and protection of the existing home. Ask how rock, unsuitable material or a change in the engineering assumptions will be measured and priced. Do not assume a generic site allowance resolves these risks.

For modular delivery, include transport to the address, lifting, road or access permissions, traffic management where needed, storage and the work joining the delivered unit to the site. Have qualified contractors assess these tasks. A delivery quote to a depot does not establish the cost of placing the dwelling on its foundations.

Services and completion

Price the required water, sewer or on-site wastewater work, electricity, communications and stormwater arrangements. Include any upgrade to the existing property that the proposal requires. Ask who reinstates paving and landscaping disturbed by trenches.

Check the finishes and external works needed for occupation and the agreed use: paths, fencing, screening, floor coverings, window coverings, appliances and any other exclusions. Include commissioning, final inspection and required completion documentation. Avoid adding an item twice if the building contract already includes it.

Contributions and authority charges

Ask the relevant authority for the current contribution plan or charge schedule, its application to the proposed development, any credit or exemption and the payment date. A charge for creating a new lot is not automatically the charge for a secondary dwelling on an existing lot.

NSW has different contribution mechanisms, including sections 7.11 and 7.12. A percentage levy is not the same as a contribution calculated under another mechanism. The departmental practice note is

useful background; the current regulation, applicable plan and any approved exception need checking for the actual development [S14]. This edition does not offer a generic charge to put into your budget.

Keep written advice supporting a zero charge. If the amount is not yet known, mark the cost unresolved and ask what information is needed to calculate it. Also ask whether indexation can apply before payment.

Funding and contingency

Add borrowing costs, interest during construction, temporary accommodation or lost income where relevant. Ask the lender when funds will be available and match that to the contract's payment dates. An affordable final total can still create a cash shortage partway through the project.

Choose a contingency after discussing the remaining risks with the relevant professionals. Define the base to which any percentage applies. An allowance calculated on the subtotal before contingency avoids a circular calculation. No percentage in this book is a recommended safety margin.

Separate the construction contingency from a household emergency reserve and ongoing maintenance. If the budget works only by spending money needed for essential household costs, revisit the scope or funding before committing.

A worked budget

Fictional example prepared 9 September 2026. Every input below is invented to demonstrate budgeting. These are not current market prices, quotations or recommended allowances. Amounts are AUD and assumed GST-inclusive where applicable.

The calculation is $150,000 + $8,000 + $18,000 + $12,000 + $5,000 = $193,000. The assumed contingency is $193,000 × 0.10 = $19,300. Adding it gives $212,300. The example assumes no financing or temporary-accommodation cost; it is not a complete budget for a reader who incurs those costs.

Now change the same fictional project. Suppose an additional quoted site item is $15,000 and the contribution is $6,000 rather than zero. The subtotal becomes $214,000. Applying the same illustrative 10% method gives $21,400 contingency and a total of $235,400. The difference is $23,100. These changed inputs are also invented, not forecasts.

The lesson is to identify missing scope and recalculate the whole budget. Keeping the building package unchanged does not keep the project total unchanged. In a real project, replace every assumption with current evidence or leave the uncertainty clearly marked.

7 Compare quotes on the same scope

A useful comparison starts with the same drawing revision, site information, intended finish and completion responsibilities. Send a consistent brief to each shortlisted supplier. Ask them to identify assumptions and exclusions rather than trying to make every answer fit a single headline price.

Understand the price description

Supply only may mean a kit or a manufactured unit with substantial work still required. A base price may assume particular site conditions and standard inclusions. A turnkey description should be tested against the contract's actual scope. Fixed price also needs to be read with its adjustment and variation clauses.

These descriptions can have contractual and consumer-law significance. Do not dismiss them as meaningless, but do not rely on the label alone. Ask the supplier to specify what must still be done and paid for before the agreed use can begin.

Compare the inclusions

Use the budget headings in Chapter 6. For each quotation, record whether an item is included, excluded, provisional or unclear. Ask for clarification wherever the quoted scope does not answer the question.

Check whether the price includes GST, freight, site works, connection distances, foundations, appliances, finishing and required documents. Ask whether a price is a quotation, an estimate or an advertised starting point, and how long it remains open.

Do not rank by price until material scope differences have been resolved. An apparent saving may pay for less work. Conversely, a more expensive quote may include an item you do not need. Compare the result you actually want.

A like for like exercise

Fictional comparison prepared 9 September 2026. The invented amounts teach addition only. They are not quotes, market estimates or assessments of any business. Assume all figures have the same GST basis.

Under these invented assumptions, Quote B's comparable subtotal is $4,000 lower despite its higher package price. Neither subtotal includes any further project costs or contingency. In a real comparison, the excluded-work figures need evidence, and the standard of the work must also be comparable.

If one supplier will not price a significant exclusion, leave that comparison unresolved. Do not invent a convenient allowance to make the table complete. Ask the relevant contractor for a quote or identify the range of uncertainty with its basis.

Use area rates carefully

A price per square metre can describe a quote, but it does not make unlike projects equivalent. Check which floor-area definition was used and whether external structures are counted. A smaller dwelling still needs items such as a kitchen and bathroom, so simple proportional scaling may mislead.

Avoid adjusting an old quote using an unsourced annual inflation percentage. Ask for a current quote for the same scope. If a supplier changes the specification with the price, record both changes.

Assess quality and accountability

Ask for the product specification and evidence supporting claimed performance. Terms such as premium, Australian compliant or cyclone rated need a defined scope and relevant documents. Have the qualified professional assessing the project decide whether the evidence is suitable.

Compare the contact arrangements, inspection access, completion obligations and approach to rectification. These may affect the practical value of an offer even where prices are close. Record why you prefer an option; a price table cannot make that judgment for you.

8 Test the financial and family outcome

A granny flat can serve a family purpose, provide rental accommodation or change how a property is used. Those outcomes need different assessments. Separate the value you place on the use from claims about financial return.

Family accommodation

Discuss accessibility, privacy, visitors, parking, noise, storage and who pays ongoing costs. Consider whether the layout can adapt if someone's needs change. Have a qualified designer assess the relevant requirements rather than treating an accessibility label as sufficient evidence.

Affordability still matters when the project is not intended to earn rent. Record who contributes to construction, who owns the resulting asset and who pays for maintenance, insurance and services. Have each affected party obtain independent advice where their interests differ.

If someone transfers money or assets for a lifetime accommodation right, ask about a formal agreement covering sale, separation, death, incapacity and a move to aged care. A granny flat interest for social- security purposes concerns an accommodation right; it is not simply the physical building. Services Australia explains how such interests can affect assessment [S15].

Ask a registered tax agent about the actual arrangement. Do not assume a family-use agreement, a rent- free arrangement or a particular building name gives a blanket tax exemption. Keep records of contributions and professional advice.

Estimate rental income locally

Ask a property manager for a written rental assessment of the proposed dwelling and its access, privacy, parking and facilities. Record the assessment date and comparable properties. An advertised asking rent is not evidence that the property achieved that rent or remained occupied.

Check lawful occupation and rental requirements before treating rent as available income. Ordinary residential letting, rooming arrangements and short-stay use may involve different obligations. Use the tenancy authority for the property's jurisdiction and obtain advice on the proposed arrangement [S32].

Allow for vacancy, letting and management, maintenance, insurance, services you pay, applicable charges and replacement of items. Consider whether the new dwelling changes the main home's rent, privacy or marketability. Do not count the new rent without considering losses elsewhere on the property.

Keep the measures separate

Gross rent is rent before expenses. Operating cash before finance and tax subtracts the operating costs you have actually included. Cash after interest is still before loan-principal repayments and tax unless those have also been deducted. State the measure rather than using the word return without a definition.

Dividing an annual figure by the incremental project cost measures it against that cost only. It is not a whole-property yield, which would need an appropriate whole-property denominator. It also does not establish capital growth or the financial outcome on sale.

A rental calculation

Fictional example prepared 9 September 2026. These inputs are invented for calculation practice, not rent forecasts, operating-cost benchmarks or a lending recommendation. They use the $212,300 fictional project cost in Chapter 6.

On these assumptions, $15,600 ÷ $212,300 × 100 is approximately 7.35%. This is the example's operating cash before finance and tax divided by its project cost. It is not a market yield or a forecast. The calculation does not model construction timing, changes in property value or the full cost of owning the land.

For a stress case, assume $400 rent for 44 occupied weeks, $8,000 operating costs and $7,000 interest. The arithmetic is $17,600 - $8,000 - $7,000 = $2,600 before tax and principal repayments. All stress- case inputs are also invented. Substitute supported assumptions for your project and consider whether the household can fund a shortfall.

Loan principal affects cash available even though it is different from an operating expense. Do not mistake a positive figure before principal and tax for money freely available to spend.

Tax and property value

Renting part of a property can have income-tax and capital-gains-tax consequences. Deductibility and apportionment depend on the facts. Ask a registered tax agent about the proposed use, records to retain and whether a valuation is needed at a particular time. The ATO's rental-property guidance is the official starting point [S16].

Land tax is a separate state or territory matter. Check the relevant revenue authority before finalising the budget. In the ACT, a rented secondary dwelling on land containing the owner's principal home can attract apportioned land tax and notification obligations [S12]. Do not generalise that treatment to another jurisdiction.

For resale value, obtain a qualified valuation or suitable property-specific advice. Construction cost does not automatically become an equal increase in property value. Lawful use, design, market demand and effects on the main home all need consideration. No uplift percentage is assumed in this edition.

Compare your alternatives

Compare the proposal with other realistic ways to meet the same need, such as modifying the main home, renting suitable accommodation or postponing the project. Use consistent assumptions and consider nonfinancial effects. Do not assume that another investment must perform better or worse.

Before relying on borrowing, obtain the lender's actual terms, conditions and release schedule. Ask an appropriately authorised adviser about options relevant to your circumstances. The decision should remain workable if costs or timing differ from the initial estimate.

9 Investigate the builder and the cover

Check the business you would contract with, the people authorised to perform the work and the cover for your specific project. Public records provide evidence about defined matters; they cannot guarantee future performance or solvency.

Match the identities

Record the legal entity, trading name, ABN and any company number. Compare them across the quote, licence, contract, insurance and payment instructions. If they differ, ask for a documented explanation and professional advice before contracting.

Use the Australian Business Register and ASIC's official searches to check the entity details and status [S33]. A trading name is not necessarily the entity that owes you contractual obligations. An active registration is not proof that the business can complete your job.

Check the licence or registration

Use the relevant building regulator's current register [S30]. Confirm the holder, status, class and conditions, and whether they authorise the proposed work. Ask the regulator if the structure of the contracting arrangement is unclear.

Do not confuse annual-turnover categories, contract-value limits and insurance eligibility. If a financial condition appears on a register, ask what it means for your project. A number relating to turnover is not automatically a maximum price for an individual contract.

Save the result with its date and recheck before a consequential commitment. Ask about the qualified supervisor and which trades will perform regulated work. Owner-building and specialist categories need their own checks rather than an assumed national rule.

Establish the project cover

Ask which statutory building insurance or warranty scheme applies to the actual contract and work, when cover must be arranged and what evidence you should receive. Confirm the certificate with the insurer or scheme administrator where possible. A general eligibility letter is not necessarily cover for your address.

Statutory warranties, insurance and a builder's voluntary warranty are different. Read the policy or scheme terms for the trigger, covered work, exclusions, limits, claim deadlines and effects of advance payments. Do not assume every granny flat, movable structure or owner-built project is covered.

Victoria's official material distinguishes the Home Warranty arrangements for eligible contracts from 1 July 2026 from earlier domestic building insurance. South Australia's guidance specifies building indemnity insurance for qualifying work requiring approval and costing $20,000 or more. Tasmania publishes assistance information and scheme developments. Use the current official material for your contract, rather than assuming a uniform national last-resort scheme [S17, S18, S19].

Also ask about construction, public liability, professional, storage and transit cover as relevant. Establish when your own building or landlord policy must change. Approval does not automatically update your insurance.

Investigate the business history

Read public records and obtain references, but distinguish evidence from suspicion. A new company, changed trading structure or complaint is a reason to ask questions, not proof of misconduct. Confirm that any adverse record concerns the same entity and that you understand its outcome.

Ask about relevant completed projects, supervision, current workload and how defects were handled. With the owner's consent, speak to previous customers about the quoted scope, changes, communication and response to problems. Ask what they would clarify before signing again.

Arrange any site visit with permission and appropriate safety arrangements. A visual visit can show you a finished result; it is not an engineering assessment. If technical quality is in doubt, use a qualified inspector.

Keep the checks practical

You can say: “Before I commit, please send the contracting entity and licence details, the proposed scope and insurance arrangements, and references for comparable completed projects. Please also identify who will supervise the work and handle questions during construction.”

If a material question remains unanswered, record it and pause the dependent decision. Pressure to pay before evidence is available should prompt further checking. A polite response is welcome, but documents and verified facts matter more than confidence or personal rapport.

10 Review the contract and payments

Have a construction lawyer review the proposed contract before you sign. Give them the quote, drawings, specifications, approval information, payment schedule and any promises made during the sale. This chapter identifies questions; it does not supply legal clauses or tell you how to terminate or withhold payment.

Confirm the complete agreement

Check the parties, address, scope and document revisions. Ask which document prevails if the plans, specification and quote conflict. Include agreed inclusions and exclusions in the contract documents rather than relying on a conversation.

Identify who obtains approvals, pays fees, arranges service work, books inspections and supplies final certificates. Ask what happens if approval requires a design change or cannot be obtained. Understand any separate design engagement and the cancellation terms before paying for it.

Check the commencement conditions, completion provisions, permitted time extensions and how delays are notified. Ask about access, site security, storage, protection of the existing home and responsibility for damage. Confirm that the payment timetable works with the lender's funding conditions.

Check the deposit rule

The following are selected official snapshots checked on 8 September 2026. They summarise covered contract types and must be read with the current source. A statutory maximum is not a recommended amount to pay. Exceptions and contract scope matter, particularly for factory work.

For a smaller Queensland contract, use the additional contract bands in the QBCC guidance rather than applying the level 2 figure. For any exception, ask the builder to identify the provision and show how the contract satisfies it. A modular label alone does not establish eligibility.

Before paying, confirm that required insurance is in place and the required certificate has been provided. NSW guidance expressly links taking a payment on covered work to the insurance requirements [S20]. Check your own jurisdiction's timing requirements through the regulator [S30].

Ask what each upfront payment is for. Relabelling a deposit does not automatically avoid the rules, but a genuine separate service or authorised third-party cost needs assessment on its own facts. Have your lawyer examine the full payment arrangement rather than simply adding every fee and declaring it unlawful.

Understand progress claims

The contract should identify when payment is due and what evidence demonstrates completion of the relevant work. Ask how factory work, stored materials and site work are treated and how the schedule complies with local requirements.

QBCC states that the number and timing of progress payments for covered contracts are negotiated and payments must relate to completed work. There is no national stage-percentage schedule supplied by this handbook [S22]. Other jurisdictions have their own requirements, so check the contract against the applicable law.

Agree how you will receive invoices and inspect or verify the work before the due date. A lender's valuation or payment approval may serve the lender's purpose without checking every contractual detail for you. Arrange any separate inspection early enough to be useful.

Independently verify changed bank details using a trusted contact method before transferring money. Keep invoices, receipts and your payment ledger with the contract records. If a claim is disputed, obtain advice promptly about the required notice and response; do not simply ignore it.

Read price adjustments carefully

A prime cost item is an allowance for an item to be selected, while a provisional sum concerns work whose cost is estimated within the contract's terms. Ask what each allowance covers, whether GST and margins are included and how the final adjustment is calculated [S23].

Check fixed-price wording alongside variations, site assumptions, escalation provisions and exclusions. Ask the lawyer to identify terms that can change the price or your ability to exit. Understanding a contract helps you make decisions; lack of understanding does not by itself make it unenforceable.

For a proposed variation, request the scope, price effect, time effect and relevant drawing change. Check the contractual and statutory approval process, including any permitted urgent-work exception. Keep an authorised record before the work proceeds where required. Do not assume every cost overrun is an owner-requested variation.

Completion and final payment

Ask what practical completion means in the contract and how it differs from lawful occupation. Establish the final inspection process, documentation, defects process and any agreed retention. A list of defects does not automatically entitle you to withhold an amount of your choosing.

Arrange independent advice promptly if the work or payment claim is disputed. Wrongful withholding, premature termination or a defective notice can create a further dispute. Have your lawyer advise on the actual contract and deadlines before acting.

Keep a final-payment decision separate from the decision to move in or let the property. Chapter 13 includes the occupation and handover checks. Neither payment nor possession substitutes for required approvals.

11 Respond to problems without losing the record

If work stops, a serious defect appears or the builder enters an insolvency process, verify what has happened and get advice promptly. The correct response depends on the contract, law, insurance and facts. This chapter is an evidence and contact guide, not a universal non-payment or termination procedure.

Deal with immediate safety

For an immediate danger, contact the appropriate emergency service or authority. Keep people away from unsafe work and use qualified professionals for safety assessments. Do not enter an unsafe site, interfere with services or attempt technical repairs yourself.

Notify the relevant insurer and obtain advice on reasonable protective measures. Where urgent action is needed, keep records of the condition, advice, work and costs. Avoid destroying evidence unnecessarily, while giving immediate safety priority.

Establish the facts

Record what you observed, the dates, relevant communications and photographs taken lawfully and safely. Distinguish a missed appointment from a verified cessation of trading. Check official company records and notices if insolvency is reported [S33].

Administration and liquidation are different processes. An administrator's appointment does not, by itself, tell you which contractual steps you may take. ASIC's creditor guidance explains the administrator's role; they are not your personal legal adviser [S26].

Contact your construction lawyer, lender and insurer or scheme administrator. Ask what notices or claims are due, whether further inspections are needed and how disputed payments should be handled. Record deadlines immediately. Do not assume negotiations extend a statutory, policy or contract deadline.

Avoid automatic reactions

Do not assume insolvency automatically gives a right to terminate. Contract provisions, insolvency law and scheme requirements can affect the answer. Likewise, do not stop every payment without advice or pay a disputed claim merely to keep the conversation friendly.

Do not seize materials, change locks, take control of the site or engage a replacement builder without advice on your rights, site arrangements and insurance requirements. Ownership of materials may differ from their physical location. Agree lawful access and any protective work.

Assemble the evidence

Keep the signed contract and variations, approved drawings, permits, reports, insurance documents, inspection records, invoices, receipts and dated communications. Prepare a factual timeline and a payment ledger showing what was invoiced and paid. Retain the original files as well as any summary.

Have a suitably qualified person document completed, incomplete and defective work where required. Ask the insurer or scheme what inspection and quotation process it requires before commissioning or changing work. A replacement quote is not itself proof of the claim amount.

Check claims and assistance

Use the scheme applying to your contract and work. Eligibility, claim triggers, time limits, exclusions and calculations differ. Do not calculate recovery simply as money paid minus the value of completed work.

For example, QBCC's non-completion guidance considers assessed completion costs and funds retained or that should have been retained, with other eligibility and timing conditions. Its deadlines require prompt checking with the scheme [S27]. This is a Queensland example, not a national formula.

If a statutory insurance claim is unavailable, ask about other contractual or consumer rights, other insurance, assistance programs and insolvency claims. Tasmania's official assistance information illustrates why no insurance should not be translated into no possible assistance [S19]. Recovery remains uncertain and may involve costs.

Plan completion with advice

Before restarting, confirm the contract position, insurer's consent where required, safety, the status of approvals and any change-of-builder process. Ask whether the plans or permits need amendment or renewal. Do not assume an approval transfers unchanged to a replacement arrangement.

Obtain a scoped completion quote and inspect the proposed division between rectification and new work. Update funding and timing. Keep the new contract and any settlement documents with the original record so the responsibilities remain traceable.

12 Investigate an import before ordering

An import needs the same land-use, site, building and occupation checks as a domestic proposal, plus import-specific work. Establish who will perform that work and what evidence they need before paying the factory.

Begin with the Australian project

Give the proposed drawings and specifications to the relevant Australian engineer and building surveyor or certifier. Ask what can be accepted, what needs redesign and how concealed manufacture must be documented. A certificate needs to match the product, scope and conditions being relied on [S02].

If the evidence cannot support the required assessment, find that out before production. Do not assume any necessary rectification will be small, possible or covered by the price. Include local installation and completion responsibilities in the plan.

Identify the supplier and contract

Establish the legal seller, manufacturing location and bank beneficiary. Clarify whether you are dealing with a factory, an agent or a trading business. Use appropriate independent checks and professional assistance for records you cannot verify yourself.

Ask for the specification, drawings, material and product schedules, quality records and inspection access. Agree how substitutions are controlled and how the delivered unit will be matched to the inspected one. A video tour can be useful, but it does not authenticate every claim or replace a defined inspection.

Have a lawyer review the applicable law, dispute forum, payment terms, title, risk, rejection, remedies and practical enforcement. Overseas businesses selling directly to Australian consumers can have Australian Consumer Law obligations, although enforcement may be difficult. Do not assume all Australian rights disappear at the border [S28].

Price the complete movement

Have a freight forwarder and customs broker identify the shipping scope, ports, handling, customs, inspection, storage and delivery assumptions. Make the named delivery location and trade term explicit in the quote. Ask what happens if the vessel, clearance or site readiness is delayed.

Include inland transport at both ends where applicable, packing, insurance, port charges, broker fees, duty and tax, possible inspections or treatment, storage, delivery to the property and lifting. Then add foundations, connections, local work and approvals. Avoid double-counting charges already included in the supplier's trade term.

Record currency, exchange-rate basis, quote date and validity. Ask how exchange-rate changes and bank charges affect the amount payable. Do not treat an online currency conversion as a locked total.

Duty and GST

Tariff classification and preferential origin are separate questions. ABF's tariff contains the relevant classifications; a trade agreement can affect treatment when its requirements are met. A supplier's location alone does not establish qualifying origin. Have the broker confirm classification, applicable rate and evidence before budgeting [S29].

GST treatment also needs checking. The statutory value of a taxable importation can include relevant freight, insurance, duty and other amounts, rather than simply the factory price. Ask the broker or registered tax agent to calculate the amount and advise on any credit entitlement. Do not assume private use or residential renting creates a GST credit [S34].

This edition deliberately gives no default import-tax total. Use the current ABF and ATO sources and obtain a calculation for the actual goods, transaction and use [S29, S34].

Check product and material requirements

Asbestos: Ask what evidence is needed to establish that the goods comply with Australia's asbestos import requirements. ABF explains representative sampling and accredited testing. A supplier declaration alone is not conclusive proof. Use competent professionals; do not take samples from suspected asbestos yourself [S35].

Electrical: Have a suitably qualified Australian electrical professional identify equipment and installation requirements, including any responsible-supplier, registration or marking obligations that apply. The EESS guidance is a starting point, not evidence that a particular supplied appliance is compliant [S36].

Plumbing: Ask the licensed plumber to check the products against the applicable WaterMark requirements and listings. Certification applies to scheduled product types and their scope. Check current lead-free requirements and local implementation as well. WaterMark is connected to plumbing installation requirements, not merely border clearance [S37].

Biosecurity: Have the broker and supplier check the current conditions for the goods and packaging. DAFF distinguishes packaging materials and applicable ISPM 15 or BICON pathways. Do not assume every timber item needs the same marking or treatment [S38].

Allocate each check to someone in writing. Customs clearance does not certify that the dwelling is ready for lawful installation or occupation.

Align payment and inspection

Ask what is verified before each payment and what contractual protection applies if goods are incomplete or nonconforming. Consider ownership, security, inspection rights, insurance and the practical ability to recover money. No payment structure should be described as risk-free.

Confirm with the lender whether overseas manufacture and advance payments are fundable and on what evidence. A finance approval for a completed property may not provide cash when the supplier demands it. Match the proposed payment dates to confirmed available funds.

Use an inspection scope agreed with the relevant Australian advisers. An inspector checking dimensions or finish is not necessarily checking every Australian requirement. Arrange the inspections before the work becomes inaccessible and before the relevant contractual acceptance deadline.

Build a realistic schedule

Obtain dated milestone estimates from each party. Separate design and approval, manufacture, inspection, export preparation, shipping, clearance, inland transport, site works and final completion. State calendar or business days and identify which stages can overlap.

Add sequential durations rather than selecting the shortest headline from each quote. Check dependencies, booking availability and what happens if the site is not ready when the unit arrives. Do not use a national manufacturing or shipping range as a delivery promise.

Before ordering, the unresolved issues should be specific and assigned: who will answer, what evidence is required and which commitment waits. If site approval, compliance evidence or the funding sequence cannot be established, postpone the order.

13 Make the next decision and plan handover

Use the record you have built to decide the next commitment. That might be commissioning a survey, paying for a design stage or signing a construction contract. The evidence needed should match the decision and the amount at risk.

Review the conditions for commitment

Write down the proposed action, its cost and whether it is reversible. Then check the matters that can prevent it from serving its purpose.

 The people signing have authority to act for the property and contracting entity.  The intended use and applicable planning and building pathway have been identified.  Required approvals for this stage are in place, with the relevant conditions understood.  The design, access, ground and service assumptions have been investigated to the necessary level.  The budget includes the agreed scope, remaining costs and explicit uncertainties.  Available funding matches the payment schedule and the household can manage the risks considered.  The builder or supplier, licence or registration and project cover have been checked.  The contract has been reviewed and material sales promises are properly recorded.  Required inspections, documents and responsibility for completion have been agreed.

A checked list is not a certificate. If an answer is missing, identify who must resolve it and what must wait. Do not average unresolved safety, legality or affordability questions into a favourable overall score.

Decide whether to proceed or revise

Record the reason for the decision. If the proposal is too costly, identify whether a smaller scope or different method actually resolves the cost rather than merely moving it outside the quote. If approval is uncertain, decide whether the next investigation is worth its fee.

Stopping after learning something material can be a sensible outcome. There is no target proportion of readers who should proceed, and no promised saving from stopping. The aim is an informed commitment, not a particular answer.

Prepare for handover during the build

Ask the builder and certifier early for the final-document checklist. Confirm the required occupation or completion authorisation, final inspections, compliance certificates and any outstanding approval conditions. The exact document names and process differ by jurisdiction; use the building regulator and the project authority [S30].

Arrange a handover inspection with the agreed scope. Record defects and incomplete items factually and follow the contract process for notifying them. Obtain advice on any payment dispute rather than making up a retention amount.

Collect the relevant approved plans, as-built information where available, product manuals, warranties, service certificates and maintenance instructions. Confirm access to switches, shut-offs, inspection points and other service items with the appropriate trades. Do not operate or alter unfamiliar equipment without its instructions.

Update the property and liability insurance for the completed building and intended use. Confirm ongoing maintenance responsibilities and budget. Keep records that future owners, occupants or advisers may need.

Before someone moves in

Confirm that the required occupation authorisation and conditions have been satisfied. A finished appearance, final invoice or delivery to the site does not establish lawful occupation.

For rental use, check the current tenancy requirements for the arrangement, including the agreement, bond process, minimum standards, safety obligations and permitted utility charging. Use the jurisdiction's tenancy authority [S32]. Obtain property-specific advice if the arrangement is unusual.

For a family arrangement, finalise the agreed rights, contributions and ongoing costs with the relevant advisers before occupation. Retain any tax or social-security advice and the records needed to support it.

Keep a usable project record

Store the final contract, approvals, drawings, inspections, payment history and completion documents together. Keep a short list of maintenance tasks and relevant warranty or claim dates from the actual documents. A deadline in a policy or contract should be recorded precisely, not inferred from a general guide.

Revisit the official sources when the proposed use changes, a new contract is signed or further development is contemplated. The evidence folder will help you explain what exists and what was approved, so the next adviser can work from facts.

Reference directory

The following directory contains the sources supporting the selected regulatory statements and the official starting points for current enquiries. Sources were reviewed on 8 or 9 September 2026 as stated. A review date is not a promise that a source will remain unchanged. Where a publication date is not stated, it is recorded as undated rather than inferred from a search result.

The book does not reproduce study-based savings, rent, yield or capital-uplift claims. Its worked budgets and calculations are original fictional examples prepared on 9 September 2026 and labelled at the point of use.

S01 ACCC consumer guarantees

Consumer rights preserved in the publication notice.

Source date: Undated guidance or live collection. Reviewed: 9 September 2026.

Consumer rights and guarantees

S02 ABCB certification and factory construction

Certificate scope and conditions; evidence is not site approval.

Source date: Live CodeMark collection; handbook announcement 2024. Reviewed: 8 September 2026.

CodeMark scheme and certificate information

Prefabricated modular and offsite construction handbook announcement

S03 Commonwealth trailer guidance

Road requirements are separate from permission to occupy land.

Source date: 19 August 2026. Reviewed: 8 September 2026.

Vehicle Standards Bulletin 1 Revision 6

S04 NSW secondary dwellings

Lot threshold, internal conversion exception, combined area test and pathway. Use the current instrument for the actual application.

Source date: Guidance updated 17 July 2025; legislation is a live consolidation. Reviewed: 8 September 2026.

Secondary dwellings guidance

Housing SEPP current text

S05 Planning Victoria small second homes

Definition, area, permit requirements, occupancy and transitional arrangements. Read the applicable scheme as well.

Source date: Live guidance and linked applicant documents; transition date stated in guidance. Reviewed: 8 September 2026.

Small second homes current guidance

Applicants guide

Planning exemption brochure

S06 Consumer Affairs Victoria surveyor appointment

Domestic builder cannot appoint a private building surveyor on the owner's behalf.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Domestic Building Consumer Guide

S07 Queensland Government secondary dwellings

State occupancy guidance and directions to local planning controls.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Planning issues and interests

Source links on this page: https://www.planning.qld.gov.au/planning-issues-and-interests · https://www.consumer.vic.gov.au/housing/building-and-renovating/plan-and-manage-your-building-project/domestic-building-consumer-guide · https://www.planning.vic.gov.au/__data/assets/pdf_file/0033/708297/DTP0604-Small-Second-Dwellings_Brochure_v5_FA_spread.pdf · https://www.planning.vic.gov.au/__data/assets/pdf_file/0035/699461/Small-Second-Dwellings_applicants-Guide_v3_FA.pdf · https://www.planning.vic.gov.au/guides-and-resources/strategies-and-initiatives/small-second-dwellings/_nocache · https://legislation.nsw.gov.au/view/whole/html/inforce/current/epi-2021-0714 · https://www.planning.nsw.gov.au/the-planning-system/housing/housing-sepp/secondary-dwellings · https://www.infrastructure.gov.au/department/media/publications/vehicle-standards-bulletin-1-revision-6-trailers-aggregate-trailer-mass-45-tonnes-or-less · https://codemark.abcb.gov.au/news/2024/new-prefabricated-modular-and-offsite-construction-handbook · https://codemark.abcb.gov.au/ · https://www.accc.gov.au/consumers/buying-products-and-services/consumer-rights-and-guarantees

S08 WA Government Residential Design Codes

Ancillary-dwelling provisions, ordinary area criterion and changed lot arrangements. Select the relevant current code part.

Source date: Live code collection with April 2026 Volume 1; information sheet 2024. Reviewed: 9 September 2026.

Current Residential Design Codes collection

Ancillary dwelling information sheet

S09 South Australia ancillary accommodation

Adopted amendment and current property-based Code enquiry.

Source date: Amendment approved 18 November 2024; Code is live. Reviewed: 8 September 2026.

Official amendment update

Adopted amendment record

Online Planning and Design Code

S10 Tasmanian Planning Commission secondary residences

Draft amendment record is not proof of commencement. Find the operative provisions and Local Provisions Schedule for the property.

Source date: Draft 01 2026 assessment record; current status must be checked. Reviewed: 8 September 2026.

AM SPP 01 2026 assessment record

Tasmanian Planning Commission

S11 ACT Government Territory Plan

Current plan, technical documents and assessment framework; no older size figure is treated as a current entitlement.

Source date: Undated guidance or live collection. Reviewed: 9 September 2026.

The Territory Plan

S12 ACT Revenue land tax

Secondary dwelling rental, apportionment and notification.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

About land tax

Land tax frequently asked questions

S13 NT Government Planning Scheme

Part 5 clause 5.4.13 dwelling-independent, including zone-dependent area limits and other conditions.

Source date: Live consolidated scheme documents. Reviewed: 8 September 2026.

Current scheme collection

Part 5 Development Requirements

S14 NSW development contributions

Background on section 7.12 levies. Current regulation and the applicable contribution plan govern; no generic levy is used in the budget.

Source date: Practice note hosted in March 2023 collection; legislation is live. Reviewed: 8 September 2026.

Section 7.12 fixed development consent levies practice note

NSW legislation current instruments

S15 Services Australia granny flat interests

Lifetime accommodation rights and social-security assessment.

Source date: Updated 26 September 2022. Reviewed: 9 September 2026.

Granny flat interest

Source links on this page: https://www.servicesaustralia.gov.au/granny-flat-interest · https://legislation.nsw.gov.au/ · https://www.planning.nsw.gov.au/sites/default/files/2023-03/section-7-12-fixed-development-consent-levies-practice-note.pdf · https://nt.gov.au/_media/docs/housing%2C-property-and-land/planning-and-development/nt-planning-scheme-2020/part-5-development-requirements-nt-planning-scheme.pdf · https://nt.gov.au/property/land-planning-and-development/our-planning-system/nt-planning-scheme · https://www.revenue.act.gov.au/rates-and-property-charges/land-tax/faqs · https://www.revenue.act.gov.au/rates-and-property-charges/land-tax/about-land-tax · https://www.planning.act.gov.au/professionals/our-planning-system/the-territory-plan · https://www.planning.tas.gov.au/ · https://www.planning.tas.gov.au/assessments-and-hearings/current-assessments-and-hearings/am-spp-01-2026 · https://code.plan.sa.gov.au/home · https://plan.sa.gov.au/have_your_say/code-amendments/view_consultation_item?catsid=10096 · https://yoursay.sa.gov.au/ancillary-student-accommodation-code-amendment/update · https://www.wa.gov.au/system/files/2024-04/info-sheet-granny-flat.pdf · https://www.wa.gov.au/government/document-collections/residential-design-codes

S16 ATO rental property tax information

Rental expenses, apportionment, capital gains and record enquiries. Apply the relevant income-year guidance.

Source date: Rental guide 2025; record guidance 2022; current ATO portal. Reviewed: 9 September 2026.

Rental properties guide 2025 in legal database

Keeping records for capital gains

ATO current guidance search

S17 Victorian Building and Plumbing Commission insurance

Contract and cover dates determine DBI or eligible Home Warranty treatment.

Source date: Updated 1 July 2026. Reviewed: 9 September 2026.

Domestic Building Insurance and Home Warranty

S18 South Australian Government builder guidance

Deposit limit and qualifying building indemnity insurance requirements.

Source date: Choosing a builder updated 10 November 2025; SAFA live guidance. Reviewed: 9 September 2026.

Choosing a builder

SAFA building indemnity insurance FAQs

S19 Tasmanian CBOS construction failure assistance

Check assistance eligibility and current insurance developments rather than assuming no recovery is possible.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Financial assistance package

S20 NSW Government residential building contracts

Deposit cap and insurance requirements before payments for covered work.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Contracts for residential building work

S21 Consumer Affairs Victoria deposits

Covered domestic building deposit bands; use the current regulator for insurance arrangements.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Deposits and payments for domestic building

S22 QBCC deposits and progress payments

Contract bands, qualifying off-site exception and progress-payment guidance.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Deposits and progress payments

S23 WA Government building contracts

Deposit cap within the stated contract-value range; allowances and progress payments.

Source date: Live guidance; factsheet hosted in October 2024 collection. Reviewed: 8 September 2026.

Building or renovating your home

Building contracts and progress payments factsheet

Building contracts guidance

S24 Tasmanian CBOS residential building contracts

Deposit bands and off-site exception. Read the current law and covered-contract scope.

Source date: Consumer guide July 2024; determination December 2016; regulations live. Reviewed: 9 September 2026.

Residential Building Consumer Guide

Mandatory contract provisions determination

Residential Building Work Contracts and Dispute Resolution Regulations

Source links on this page: https://www.legislation.tas.gov.au/view/whole/html/inforce/current/sr-2016-089 · https://www.cbos.tas.gov.au/__data/assets/pdf_file/0015/405006/Directors-determination-Mandatory-Contract-Provisions-Dec-2016.pdf · https://www.cbos.tas.gov.au/__data/assets/pdf_file/0020/405038/Residential-Building-Consumer-Guide-July-2024-Final.pdf · https://www.wa.gov.au/sites/default/files/announcements/building-contracts · https://www.wa.gov.au/system/files/2024-10/building_contracts_progress_payments.pdf · https://www.wa.gov.au/organisation/building-and-energy/building-or-renovating-your-home · https://qbcc.qld.gov.au/home-owner-hub/build-renovate/contracts-payments/deposits-progress-payments · https://www.consumer.vic.gov.au/licensing-and-registration/builders-and-tradespeople/running-your-business/deposits-and-payments · https://www.nsw.gov.au/housing-and-construction/building-or-renovating-a-home/preparing/contracts · https://cbos.tas.gov.au/topics/housing/buying-selling-property/financial-assistance-package-for-consumers-affected-by-construction-failures?SQ_VARIATION_649248=0 · https://safa.sa.gov.au/building-indemnity-insurance/faqs · https://www.sa.gov.au/topics/housing-and-property/buying-building-selling/building-a-home/choosing-a-building-professional · https://www.bpc.vic.gov.au/home-owners/insurance-for-domestic-building-work/domestic-building-insurance-and-home-warranty · https://www.ato.gov.au/ · https://www.ato.gov.au/forms-and-instructions/capital-gains-tax-guide-2022/part-a-about-capital-gains-tax/keeping-records · https://www.ato.gov.au/law/view/document?LocID=%22SAV%2FRENTAL%2FATAPPORTIONMENTOFRENTALEXPENSES%22&PiT=99991231235958

S25 NT Government prescribed residential contracts

Maximum deposit in the prescribed residential contract framework.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Signing a residential building contract

S26 ASIC voluntary administration

Administrator role and creditor process; obtain contract-specific advice.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Voluntary administration a guide for creditors

S27 QBCC non completion claims

Eligibility, deadlines and assessed completion cost approach.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Home warranty non completion

S28 ACCC overseas purchases

Australian consumer obligations can apply to overseas sellers; practical enforcement can be difficult.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Buying online

S29 Australian Border Force tariff and origin

Classification and preferential origin are separate. Confirm actual treatment with the broker.

Source date: Live tariff and trade agreement guidance. Reviewed: 8 September 2026.

Chapter 94 tariff

China Australia Free Trade Agreement

S30 Building regulator enquiry directory

Use the relevant regulator for licensing, owner-building, project cover, inspections and completion. These are official enquiry starting points, not a national set of rules.

Source date: Undated guidance or live collection. Reviewed: 9 September 2026.

NSW housing and construction

Victoria Building and Plumbing Commission

Queensland QBCC

WA building or renovating

South Australia Consumer and Business Services

Tasmania CBOS

ACT Access Canberra

NT Building Practitioners Board

S31 ABCB National Construction Code

Code structure, state and territory adoption and variations. Confirm the applicable edition with the local administration.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

General NCC frequently asked questions

Current NCC editions and resources

Source links on this page: https://ncc.abcb.gov.au/ · https://ncc.abcb.gov.au/faq/general-ncc · https://bpb.nt.gov.au/ · https://www.accesscanberra.act.gov.au/ · https://www.cbos.tas.gov.au/ · https://www.cbs.sa.gov.au/ · https://www.wa.gov.au/organisation/building-and-energy/building-or-renovating-your-home · https://www.qbcc.qld.gov.au/ · https://www.bpc.vic.gov.au/ · https://www.nsw.gov.au/housing-and-construction/rules · https://www.abf.gov.au/fta/Pages/fta-countries/china.aspx · https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff/schedule-3/section-xx/chapter-94 · https://www.accc.gov.au/consumers/buying-products-and-services/buying-online · https://www.qbcc.qld.gov.au/complaints-disputes/building-work-issue/non-completion-building-work/home-warranty-non-completion · https://www.asic.gov.au/regulatory-resources/insolvency/insolvency-for-creditors/voluntary-administration-a-guide-for-creditors · https://nt.gov.au/property/building/build-or-renovate-your-home/building-and-renovating-a-home/signing-a-residential-building-contract

S32 Tenancy enquiry directory

Current agreements, bonds, standards, safety and charging requirements. Select the jurisdiction and actual accommodation arrangement.

Source date: Undated guidance or live collection. Reviewed: 9 September 2026.

NSW housing rules

Victoria renting

Queensland Residential Tenancies Authority

WA renting tools and guidance

South Australia Consumer and Business Services

Tasmania CBOS

ACT Access Canberra consumer enquiries

NT Consumer Affairs

S33 Official business records

Entity identity and public status checks do not certify financial health.

Source date: Undated guidance or live collection. Reviewed: 9 September 2026.

Australian Business Register ABN Lookup

ASIC register searches

NT building practitioner register

S34 ATO import GST

Taxable importation valuation and tax enquiries; credit eligibility requires separate assessment.

Source date: GSTR 2003 15; linked point-in-time text 27 July 2022. Reviewed: 8 September 2026.

GSTR 2003 15 importation ruling

ATO current tax guidance

S35 Australian Border Force asbestos

Representative sampling and accredited testing guidance.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Sampling and testing for asbestos

S36 Electrical Equipment Safety System

Supplier and equipment compliance framework; installation and jurisdiction requirements also need checking.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Steps for compliance with EESS

S37 ABCB WaterMark and lead free products

Scheduled product certification, installation and lead-free requirements. Check actual product and local implementation.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Installation and WaterMark licensing

Lead free plumbing products

S38 Department of Agriculture Fisheries and Forestry biosecurity

Packaging conditions, relevant ISPM 15 or BICON pathways and current import checks.

Source date: Undated guidance or live collection. Reviewed: 8 September 2026.

Timber packaging requirements

Source links on this page: https://www.agriculture.gov.au/biosecurity-trade/import/goods/timber-packaging · https://watermark.abcb.gov.au/ncc-navigator/lead-free-plumbing-products · https://watermark.abcb.gov.au/plumbers/installation-and-watermark-licensing · https://www.eess.gov.au/equipment/selling-electrical-equipment-in-australia/steps-for-compliance-with-eess/ · https://www.abf.gov.au/importing-exporting-and-manufacturing/prohibited-goods/asbestos/sampling-and-testing-for-asbestos · https://www.ato.gov.au/ · https://www.ato.gov.au/law/view/document?LocID=%22GST%2FGSTR200315%2FNAT%2FATO%2Fft70%22&PiT=20220727000001 · https://www.ntlis.nt.gov.au/building-practitioners/ · https://www.asic.gov.au/online-services/search-asic-registers · https://abr.business.gov.au/ · https://consumeraffairs.nt.gov.au/ · https://www.accesscanberra.act.gov.au/ · https://www.cbos.tas.gov.au/ · https://www.cbs.sa.gov.au/ · https://www.consumerprotection.wa.gov.au/renting-tools-and-checklist · https://www.rta.qld.gov.au/ · https://www.consumer.vic.gov.au/housing/renting · https://www.nsw.gov.au/housing-and-construction/rules