How to Compare Builder Quotes for a Renovation in NZ

Start with one project brief

A fair comparison starts before you look at the prices.

MBIE says contractors can prepare more reliable quotes when they have detailed drawings, specifications and relevant information about the site. It also recommends checking that competing quotes cover the same scope, materials and fixtures.

Ideally, each builder should have received the same:

• project brief;
• plans and drawings available at the time;
• specifications;
• known site information;
• product selections already made;
• list of work you expect to be included.

If Builder A priced one version of the job and Builder B priced another, comparing the headline totals will tell you very little.

If you do not yet have one clear scope to compare the quotes against, use SeekSaver's Home Renovation Project Brief Checklist NZ first.

First check: is it a quote or an estimate?

Do not assume every pricing document has the same meaning.

An estimate is an informed approximation of what the work may cost. It is not a fixed price. Official consumer guidance says estimates should be based on reasonable information and important limitations or possible variation should be made clear.

A quote is an offer to do specified work for a specified price. Once accepted, it can form a contract. A provider cannot simply increase the price for the same quoted work because they underestimated it, although agreed extra work, scope changes or other agreed contractual changes can affect what you eventually pay.

On your comparison worksheet, record each document as:

• Quote
• Estimate
• Unclear

If one builder has provided an estimate and another a detailed quote, recognise that difference before comparing their totals.

Compare the scope before the total

Now put the quotes beside the same project brief.

MBIE recommends comparing the details to make sure the quotes cover the same building work, materials and fixtures.

For each major part of your renovation, mark what each quote says.

What is included?

Look for work clearly included in the returned document.

Depending on your particular renovation, examples might include demolition, building work, particular trades, equipment, waste removal or other project-specific work.

These are comparison examples, not mandatory items that must appear in every renovation quote.

Do not assume something is included simply because another builder has priced it.

What is excluded?

An exclusion can explain why one total appears lower.

Record exclusions exactly as the quote describes them.

Also look for phrases such as:

• “by owner”;
• “client supplied”;
• “not included”;
• “others to arrange”;
• “excluded unless required”.

An exclusion is not automatically a problem. The problem is comparing one quote that includes the work with another that leaves it elsewhere without noticing.

What is unclear?

“Not mentioned” is not the same as “included” or “excluded”.

Mark it Unclear.

That gives you a question to send back rather than an assumption to build your decision on.

Check materials, fixtures and other specifications

Quotes can differ because the builders are not pricing the same products or finish level.

MBIE specifically tells homeowners to compare materials and fixtures as part of a like-for-like quote review. It also notes that contractor sourcing choices and unspecified products can affect quoted figures.

Check whether each quote identifies the same:

• specified products;
• materials;
• fixtures;
• finishes;
• performance or quality requirements where these have already been decided.

For example, if one quote prices the exact product specified in your plans while another uses a generic allowance, those lines are not yet directly comparable.

Do not decide which material is “better” from the quote comparison alone.

First make the difference visible.

Put GST and allowances on the same basis

Three totals can look surprisingly different simply because the documents present money differently.

GST

The Commerce Commission says quotes and estimates should be inclusive of GST, and MBIE tells homeowners to check whether GST is included.

For each returned quote, record:

GST included: Yes / No / Unclear

If the treatment is unclear, ask before comparing the totals.

Provisional sums

A provisional sum is an allowance for specific building work where there is not yet enough information to provide a fixed amount.

MBIE recommends checking that the allowance is appropriate for what you are expecting.

When comparing provisional sums, do not ask only:

Which allowance is bigger?

Ask:

• What work does it cover?
• What is still unknown?
• Are the builders allowing for the same scope and quality?
• What happens when the actual requirement is known?

A smaller provisional sum does not automatically make a proposal better or worse. It may simply represent a different assumption.

Prime cost / PC sums

A prime cost sum, often written as a PC sum, is an allowance for an item that has not yet been finally selected.

MBIE gives the example of a fixture that the homeowner will choose later. If the selected item costs more than the allowance, the extra cost will need to be dealt with. MBIE also notes that a PC sum does not include installation unless that is stated.

For each PC sum, compare:

• the item being allowed for;
• the allowance shown;
• the type or quality assumed;
• whether installation is included;
• anything else the quote says the allowance covers.

If a quote simply says “allowance” without enough explanation, mark it Unclear and ask what it means.

Compare responsibilities and timing assumptions

Two quotes can contain different amounts because they allocate work differently.

MBIE notes that building arrangements can differ—for example, full contract, labour-only and managed labour-only arrangements can place different responsibilities on the builder and homeowner.

You do not need to analyse the full future contract at this stage.

For quote comparison, identify what each returned proposal appears to assume about matters such as:

• owner-supplied items;
• subcontractor work;
• consent or inspection coordination where relevant;
• project management;
• other work assigned to third parties.

Again, these are not mandatory quote headings. Compare only what is relevant to your project.

Also record any timing information actually supplied, such as:

• proposed start period;
• expected programme or duration;
• assumptions that must be met before work begins.

Do not treat a missing programme as if it were a promise.

Mark it Unclear if timing matters to your decision.

When the numbers are very different, find the reason

MBIE and Consumer Protection both recommend asking why where returned quotes differ materially.

Possible explanations include:

• different materials;
• different assumptions;
• different scope;
• different estimates of the work involved;
• misunderstanding the project.

Do not automatically conclude:

• the lowest quote is missing work;
• the highest quote is overpriced;
• the middle quote is safest.

The documents alone do not prove any of those things.

Instead, work through the comparison sheet and identify where the differences actually sit.

For example:

Those totals are not yet describing exactly the same position.

Do not invent a price for the missing painting or substitute your own figure for the PC sum.

Instead:

1. identify the exact difference;
2. ask Quote A's builder to clarify what the PC sum covers and confirm the painting exclusion;
3. ask Quote B's builder to confirm the specified fixture and painting scope;
4. where clarification materially changes a proposal, ask for an updated written quote or written comparable position;
5. compare the updated documents again.

The principle is:

Normalise the information, not the price.

Turn every unclear difference into one question

The worksheet should produce a clarification list.

For each important difference, write one specific question.

Examples:

• “Does this amount include GST?”
• “Is painting included or excluded?”
• “What work is covered by this provisional sum?”
• “Does this PC sum include installation?”
• “Which exact flooring product have you allowed for?”
• “Is the electrician included in this figure?”
• “Who is arranging the inspection shown in the brief?”
• “What assumption explains the difference in this line?”

Where clarification changes the proposal materially, ask for the revised position in writing so you have a current document to compare.

Do not silently modify or reconstruct the quote yourself.

Keep builder evaluation separate

A detailed quote does not prove that a builder is experienced, properly licensed for relevant work, reliable or suitable for your renovation.

Those are separate provider questions.

If that part of your decision is incomplete, use SeekSaver's Questions to Ask a Builder Before a Renovation NZ.

This guide is only assessing the returned proposal.

That separation matters because a homeowner can reach two different conclusions:

This is the clearest quote.

and:

This is the builder I want to work with.

They are related decisions, but they are not the same decision.

Builder Quote Comparison Worksheet

Use the worksheet below for up to three returned proposals.

For most comparison rows, classify each quote as:

Included · Excluded · Unclear · Not applicable

Where the row asks for a value or description, copy what the quote actually says rather than guessing.

The final column is:

Clarification needed / question to ask

The aim is not to calculate a winner.

The aim is to expose differences.

After you identify the proposal you want to progress

Choosing which proposal you want to progress is not the end of the process.

It is also important to be careful with the word “accept”. Accepting a quote can itself create a contract.

The intended SeekSaver journey is:

Compare → clarify → identify the proposal you want to progress → review the final written agreement → only then formally accept or sign anything that may bind you.

Use SeekSaver's Renovation Contract Checklist NZ: What to Check Before You Sign for that next stage.

If your plans, scope or responsibilities are still changing enough that quote comparison is premature, return to the Renovation Planning Stages Checklist NZ.