A low price can look like a win until work begins and you discover it did not include waste removal, plastering, building control fees or the fittings you expected. This builder quote review guide helps you compare like for like, ask the right questions and choose a local builder with confidence.

Start with the work, not the total

A quote is only as useful as the brief behind it. If one builder has priced from a detailed plan and another has worked from a short conversation, their totals may be impossible to compare fairly. The cheaper figure may simply cover less work.

Before reviewing prices, write down what you want completed. Include room dimensions where relevant, finishes you expect, whether materials are supplied, access restrictions, and any work that needs to happen before or after the main build. For an extension, that could mean groundwork, drainage, steelwork, insulation, windows, plastering and making good external areas. For a bathroom alteration, it may include plumbing changes, tiling, electrics, ventilation and waste disposal.

You do not need to know every technical detail. You do need enough clarity for each builder to price the same job. If plans, structural calculations or a schedule of works are available, send the same documents to every contractor.

What a clear builder quote should show

A professional quote should make it easy to see what is included, what is excluded and where the price may change. It does not have to be pages long, but a single line saying “rear extension - £45,000” gives you very little protection from misunderstandings.

Look for a written breakdown covering labour, materials and the key stages of the job. It should state whether VAT is included, give an estimated start date and duration, and explain the payment schedule. For larger jobs, the builder may separate costs for demolition, foundations, brickwork, roofing, internal works and finishing.

Pay close attention to allowances. A provisional sum is an estimate for work that cannot yet be priced accurately, such as unforeseen drainage repairs. A prime cost allowance is usually a budget for a product you will choose later, such as sanitaryware or tiles. Neither is automatically a problem, but both can increase the final bill. Ask what assumption sits behind each allowance and what happens if the actual cost is higher.

Also check exclusions. Builders often exclude planning fees, building control charges, utility-company work, decorating, landscaping or specialist surveys unless they have explicitly included them. An exclusion is not a warning sign if it is clear from the outset. A vague quote is the bigger risk.

Compare the scope line by line

Put each quote next to your original brief and compare the details, not just the grand total. Is one quote supplying insulation to a different specification? Has another included scaffolding, skips or site protection? Are windows, doors and finishes described by type and quality?

Where a quote is unclear, ask for it to be clarified in writing before accepting it. Do not assume a builder has included something because it seems obvious to you. Good contractors expect questions and should be comfortable explaining their proposal.

Why the cheapest quote is not always best

A quote well below the others deserves a closer look. It may be a genuine saving because the builder has good supplier rates, has a gap in their schedule or uses a more efficient approach. But it can also mean missed items, unrealistic labour costs or an intention to recover the difference through variations later.

Equally, the highest quote is not always the safest choice. It may include a larger contingency, premium materials or work you have not asked for. Ask each builder to explain major differences. Their answer can reveal how carefully they have considered the job.

A sensible decision balances price with the scope, programme, communication and evidence that the contractor can deliver similar work. You are choosing someone who may be working in or around your home for weeks or months, not simply buying a product off a shelf.

Check the builder behind the figure

A detailed price matters, but so does the person or business giving it. Confirm the builder’s full trading name, contact details and who will manage the site day to day. If a limited company is quoting, make sure the contract will be with that company rather than an unclear third party.

Ask for recent examples of comparable work and, where practical, speak to previous customers. Recent references are more useful than testimonials from years ago because they show how the builder currently manages communication, delays and aftercare. For substantial projects, viewing a completed job can help you judge finish quality.

Insurance should match the work being carried out. Public liability insurance is a common starting point, while employers’ liability may be relevant where the builder has employees. For structural work, ask how the builder handles warranties, specialist design and building control requirements. The right answer depends on the project, so be wary of anyone who promises that paperwork never matters.

Using a service that focuses on verified trades, such as VeriTrade UK, can give you a stronger starting point when searching locally. Verification does not replace your own checks, but it helps reduce the uncertainty that comes with hiring from an unverified advert or recommendation alone.

Agree payments and changes before work starts

A fair payment schedule follows progress. A modest deposit may be reasonable where the builder needs to book labour or order bespoke materials, but a request for most of the project cost upfront should prompt questions. For larger projects, staged payments linked to visible milestones are usually easier to manage than fixed weekly requests with no agreed measure of progress.

Your written agreement should state the total price or pricing basis, scope of work, start date, expected completion date, payment stages and how changes will be approved. It should also say who is responsible for ordering materials, arranging waste removal and managing any subcontractors.

Changes are common in building work. Hidden defects can appear once walls, floors or old fittings are opened up, and homeowners sometimes change their mind on finishes. The key is not to avoid every variation. It is to agree the cost and impact on the programme before extra work begins, wherever possible.

A simple written variation record should describe the change, price it, and confirm whether it affects the completion date. This prevents a verbal agreement being remembered differently later.

Questions to ask before accepting a quote

Ask these questions if the quote does not already answer them:

• What exactly is included in the price, and what is excluded?
• Is VAT included, and are there any provisional sums or product allowances?
• Who will be on site each day, and will subcontractors be used?
• What are the start date, expected duration and key payment stages?
• How will additional work or unforeseen issues be priced and approved?
• What insurance, approvals and certificates apply to this project?

The responses matter as much as the wording. A builder who gives direct, consistent answers before the job starts is more likely to communicate well if a problem arises during the work.

Watch for warning signs

You do not need to reject a quote because it is brief or because the builder is busy. Some excellent local tradespeople are more practical than polished on paperwork. However, do not move ahead until the essentials are clear.

Be cautious if a contractor pressures you to decide immediately, will not put the price in writing, asks for cash only, cannot explain a very low quote, or refuses to discuss insurance and previous work. A reluctance to clarify the basics can become expensive once work has begun.

There is also a difference between a quote and an estimate. A quote is normally a fixed price for an agreed scope, subject to stated conditions and changes. An estimate is a best guess and can move more easily. If the document uses both terms, ask which one applies and what could make the price change.

Make the decision you can stand behind

Once you have checked the scope, allowances, credentials and payment terms, choose the builder who gives you the clearest route to a well-managed job. That may be the lowest comparable quote, but it may be a slightly higher one that includes better detail, realistic timings and proven experience with your type of property.

Keep the accepted quote, messages, drawings and variation approvals together from the first day. Clear records and clear expectations give a good builder the best chance to do good work - and give you a practical way to keep your project on track.