Building Quote Checklist Australia (2026): What a Builder's Quote Must Include

Most building disputes in Australia do not start on site. They start in the quote, with something that was never written down: a tile allowance nobody checked, a "site preparation excluded" line nobody read, a deposit paid before the insurance existed. The state tribunals that hear these cases (NCAT, VCAT, QCAT) see the same handful of gaps over and over.

This is the checklist a good builder's quote already satisfies, and the one a homeowner should run before signing anything. It applies to renovations, extensions, new builds and any job that needs a building licence, from a $15,000 deck to a $600,000 knock-down rebuild.

1. The builder is licensed for this job, in this state

Every state licences builders, and the licence has classes and limits. A licence to build low-rise residential work is not a licence for structural alterations, and a "carpentry" licence does not cover a full extension.

Check the licence number on the public register before you compare prices:

• NSW: NSW Fair Trading licence check. Residential work over $5,000 needs a licensed contractor; over $20,000 the builder must hold Home Building Compensation Fund (HBCF) cover for the job.
• Victoria: Victorian Building Authority register. Domestic work over $10,000 needs a registered builder; over $16,000 requires Domestic Building Insurance.
• Queensland: QBCC licence search. Work over $3,300 needs a QBCC licence and Home Warranty Insurance.
• WA, SA, ACT, TAS, NT: each has an equivalent register and threshold.

Confirm the licence is current, in the name of the entity on the quote (not a mate's licence), and covers the class of work. A quote from "Smith Building" backed by a licence in the name of "J. Smith Carpentry" is a question to ask before you go further.

2. Home warranty insurance is named and dated

Above the state threshold, the builder must take out home warranty insurance (called HBCF in NSW, DBI in Victoria, Home Warranty in Queensland) for your specific job, and give you the certificate before taking a deposit or starting work. It protects you if the builder dies, disappears or becomes insolvent partway through.

The quote or contract should state that the policy will be issued, and the certificate must arrive before any money changes hands. "We are covered" is not a certificate.

3. The scope is written, not described

A quote that says "renovate kitchen and bathroom as discussed" is unenforceable. A quote you can hold someone to lists:

• Each area of work and what is done to it (demolish, frame, plaster, tile, paint)
• Drawings or plans referenced by number and date
• The specification schedule: product names, models, grades and colours for windows, doors, cladding, roofing, tiles, tapware, appliances, flooring and paint
• What is excluded, explicitly

If a finish has not been chosen yet, it appears as an allowance (see item 5). If it is not on the page, assume it is not in the price.

4. Fixed price, cost-plus, or a mix

A fixed price (lump sum) contract means the builder has priced the scope and carries the risk of getting it wrong. It is the right structure for a defined job with plans and engineering complete.

Cost-plus means you pay actual costs plus a margin (usually 15 to 25 percent). It suits genuinely unknown work, such as a heritage restoration where nobody knows what is under the floor, and it is a bad idea for a standard extension because every overrun is yours.

Some contracts are fixed price with cost-plus sections for defined unknowns (excavation in rock, for example). That is fine if the unknown is small and clearly bounded.

Know which one you are signing. Builders sometimes present a cost-plus quote as an "estimate" and homeowners read it as a fixed price.

5. Allowances are realistic, and listed separately

Provisional sums (allowances for work not yet scoped, like excavation) and prime cost items (allowances for products not yet chosen, like tiles at $45 per square metre) are where cheap quotes hide. Two quotes for the same plans can be $30,000 apart purely because one builder allowed $8,000 for a kitchen and the other allowed $30,000.

For every allowance, ask: is this what the product I actually want costs? Take the tile allowance to a tile shop. Take the appliance allowance to a showroom. If the allowance is half what you would spend, the quote is half what you will pay.

6. The deposit is legal and the payments follow the work

Deposits are capped by law for domestic building work: 10 percent in NSW (5 percent above $20,000 in some cases), 5 percent in Victoria for work over $20,000, 10 percent in Queensland. A builder asking for 20 or 30 percent up front is either cash-flow stressed or unaware of the law. Neither is a good sign.

Progress payments must be tied to completed stages, not dates on a calendar. The standard stages are deposit, base or slab, frame, lock-up (roof on, windows and external doors in), fixing (plaster, cabinets, tiling), and practical completion. Each claim should reference the stage and you should be able to see it is done before you pay. A schedule that front-loads 60 percent of the price into the first two stages leaves you exposed if the builder stops.

Keep a final payment (5 to 10 percent) until practical completion and the defects list is agreed.

7. Variations have a process

Every job has changes. The contract needs to say how they happen: in writing, priced before the work is done, signed by both parties. Verbal variations are the single biggest source of end-of-job disputes; the builder remembers agreeing to a price and you remember agreeing to look at it.

A reasonable variation margin is 10 to 20 percent on the cost of the change. A contract that lets the builder charge "reasonable costs" for variations without a written price has no ceiling.

8. Start date, finish date and what happens if it slips

The contract should give a commencement date, a number of build days or a completion date, and a list of what legitimately extends the period (weather, variations, supplier delays). It should also say what you receive if the builder is late without cause. Liquidated damages of $150 to $500 a week are common in standard contracts and are worth insisting on for a job where you are renting elsewhere.

Ask the builder for the actual durations of their last three completed jobs. It tells you more than the number in the contract.

9. Defects, warranty and the statutory periods

Every state gives homeowners a statutory warranty on residential building work, regardless of what the contract says: in NSW it is 6 years for major defects and 2 years for other defects; Victoria 10 years for structural; Queensland 6 years and 6 months for structural. The builder cannot contract out of these.

On top of that, the quote should state the builder's own defects liability period (typically 13 weeks to 12 months after completion) during which they return to fix anything on the defects list at no cost. Get the process for reporting defects in writing.

10. Insurance beyond home warranty

The builder should hold public liability insurance (usually $10 million to $20 million) and construction works or contract works insurance covering the site while the job is underway. Ask for the certificates of currency. If a wall collapses onto the neighbour's car or a storm takes the half-built roof, this is what pays.

Your own home insurance often does not cover a property under major renovation. Tell your insurer before work starts.

Red flags that end the conversation

• A deposit above the legal cap, or any payment requested before the home warranty certificate is issued
• No licence number on the quote, or a licence in a different name
• "Cash price" offered for a discount: no insurance, no warranty, no recourse
• A quote with no exclusions listed at all (nothing is included in everything)
• Allowances that are obviously below the cost of what you have discussed
• Pressure to sign this week to "hold the price"

The bottom line

A building quote is a legal document you will live with for six months and a warranty period after that. The licence, the insurance certificate, the specification schedule, realistic allowances, a lawful deposit and stage-based payments are not negotiable extras; they are what separates a builder from a risk. If the quote in front of you is missing any of them, ask for them before you compare the price.