Comparing quotes
Why do two builders
quote the same job
$80,000 apart?
Usually because they are not quoting the same job. Quote spread on residential renovation is rarely about one builder being greedy and another being cheap — it is about what each has included, what each has assumed, and how much risk each has priced.
The five real reasons
Provisional sums
An allowance for something not yet specified — tiles, joinery, the kitchen. A builder who allows $18,000 for a kitchen and one who allows $45,000 produce very different totals for identical drawings. This is the single largest source of spread.
Exclusions
Read what each quote leaves out before you read the number. Landscaping, driveway reinstatement, temporary accommodation and site remediation are commonly excluded — by one builder and not the other.
Risk pricing
A builder who has been under the house and found rot will price it. One who has not will either exclude it or discover it later as a variation. The lower quote is not always the cheaper job.
Program and overheads
A builder with a full book prices to be busy, not to win. One with a gap prices to fill it. Neither is dishonest; you are seeing their capacity, not your project.
The fifth reason is simpler: some builders do not want the job and quote high rather than decline. A quote well outside the others is often a polite no.
How to make quotes comparable
| Ask for | Why it matters |
|---|---|
| A full schedule of provisional sums | Reveals where the real difference sits, and lets you equalise allowances across quotes |
| The exclusions list in writing | Cheapest quote plus its exclusions is often the most expensive quote |
| A written variations policy | Tells you what happens when something is found, before it is found |
| Their allowance for site access | The spread in these answers tells you who has actually visited |
| A construction program | Time is money on a project you may be renting through |
The thing to do first
Have an independent cost expectation before you receive a single quote. Not because builders are dishonest, but because a number without a reference point is impossible to judge. If you know the job should land between $285,000 and $385,000, a $240,000 quote prompts a question about exclusions rather than a celebration.
Have a number before they quote
An indicative range gives you the reference point that makes quote comparison possible.
Common questions
Why is one builder $80,000 cheaper than another?
Most often because of provisional sums and exclusions rather than margin. A lower allowance for joinery, tiles or the kitchen, or an exclusion for site works one builder has priced and another has not, easily accounts for that spread on the same drawings.
Should I always take the cheapest quote?
Not without equalising the allowances first. The cheapest quote plus its exclusions and provisional sum shortfalls frequently ends up the most expensive job. Compare inclusions before comparing totals.
What is a provisional sum?
An allowance for an item not yet fully specified. If the eventual cost exceeds the allowance, you pay the difference. Two builders using different allowances for the same item produce very different quotes for identical work.
How many quotes should I get?
Three is the usual advice and it holds, provided all three are quoting the same documented scope. Three quotes on three different assumptions tells you nothing useful.
Related
When you are ready to build
AE Index is not a building company. When a project is ready to be priced properly, we pass it to a builder from our verified network — who will walk the site, inspect what is under the floor, and put a fixed price in writing. We are paid a fee by them on work that proceeds, and you are under no obligation to use them.
- Current domestic builder registration, confirmed with the Victorian Building Authority
- Domestic building insurance current and sighted
- Two completed projects contacted directly — not supplied testimonials
- Fixed-price contracts with a written variations policy
- Re-checked annually, and removed from the network on any lapse
Last updated 28 July 2026