How to compare builders’ quotes when the prices and inclusions differ
By Build Advocate
To compare builders’ quotes properly, first check that they price the same work. Put the drawings, specifications, inclusions, exclusions and allowances alongside each other before comparing the totals. Then examine how each builder proposes to deliver and fund the job.
A detailed comparison should leave you with fewer unknowns—not simply a preferred price.
Start with the information each builder received
Were all builders sent the same drawing revisions and specification? Did one visit the property while another priced from planning drawings? Has the design changed since the earliest quote?
Record the drawing references and dates behind each proposal. If the information differs, ask for the affected prices to be updated against a common scope. Otherwise you may be comparing different projects.
Put the scope side by side
Use this checklist and ask each builder to clarify the gaps in writing.
Structural work: Which design, steelwork, floor and roof alterations are included?
Access and setup: Are scaffolding, deliveries, skips, protection and welfare included?
Plumbing and electrics: What points, fittings, connections and testing are allowed for?
Finishes: Which plastering, decoration, joinery and floor finishes are included?
Client purchases: Who buys sanitaryware, tiles, kitchen fittings and other selected items?
Completion: What making good, removal of waste and handover information are included?
Tax and other costs: Is VAT included where applicable, and which professional or statutory fees sit outside the quote?
Avoid treating a blank entry as either included or free. Mark it as unconfirmed until the builder explains it.
Separate fixed prices from allowances
An allowance gives part of the project a provisional value. Its usefulness depends on what it covers and how it will be adjusted.
For each allowance, ask what quantity and specification it assumes, whether installation is included, and what happens if the selection or actual work costs more or less. Check whether overhead, profit and VAT will also affect the adjustment.
An allowance that is too low can make a proposal look attractive today while leaving you with a larger bill later. That does not mean every allowance is unreasonable: some work cannot be fully priced until more information is available.
A worked comparison
These figures are invented to demonstrate the method. They are not market rates or a real customer's quotations. Assume the same tax basis throughout.
Builder A
Headline total: £80,000
Scaffold omitted from headline: £5,000
Decoration omitted from headline: £3,000
Adjustment to the same bathroom allowance: £2,000
Comparison total: £90,000
Builder B
Headline total: £87,000
Scaffold: included
Decoration: included
Adjustment to the same bathroom allowance: £0
Comparison total: £87,000
Builder A's headline is £7,000 lower. With those scope differences included, its comparison total is £3,000 higher. In a real assessment, obtain evidence for every adjustment rather than filling the gaps with convenient guesses. Unpriced uncertainty should remain visible.
The adjusted total is still only one part of the decision. It does not establish workmanship, availability or the reliability of either builder.
Check the programme and payment proposal
Ask who will be working on the project, what work can overlap, and which deliveries or decisions control the finish date. A short duration needs a credible delivery method behind it.
Look at when payments become due and what they fund. Early procurement and mobilisation may need money before visible construction progresses, but the scope, timing and evidence should be clear. Later payments should relate to defined work or agreed commitments. A standard percentage alone does not explain whether a payment plan suits your job.
Check the builder as well as the document
Confirm the identity of the business you will contract with, relevant experience, references and the proposed team. Ask about comparable projects, not just attractive photographs. Establish who communicates with you, handles changes and resolves incomplete or defective work.
Before choosing, get one clarified version
Bring accepted clarifications into the quotation, scope and proposed contract documents. Important promises scattered across texts and conversations are harder to track during construction.
You should be able to explain what you are buying, what remains uncertain, who is responsible for each part and how changes will be handled.
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