hammerscore
Hiring guides · 4 min read · 1 July 2026

How to Choose a Builder: 7 Checks Before You Hire

Builders handle everything from extensions and loft conversions to structural repairs and garden walls. The trade is unlicensed in the UK, so reputation, insurance and paperwork carry almost all the weight when choosing one. These seven checks take less than half an hour and filter out most of the operators you'd regret hiring.

1. Read reviews across more than one platform

Search the company name plus “reviews” and look at several sources, not just the one the company links to. Hammerscore company pages for builders combine ratings from multiple platforms into one score with links to the originals.

Read the negative reviews first. What matters is whether the same complaint repeats and how the business responds — a calm, specific reply is a good sign; blaming every customer is not.

2. Verify the credentials that matter

There is no legal registration scheme for general building work, but TrustMark endorsement and Federation of Master Builders membership are checked credentials you can verify on the organisations' own websites.

3. Confirm insurance

Ask to see a current public liability insurance certificate. This covers damage to your property and injury to others. For larger jobs, also ask how your deposit is protected and whether any guarantee is insurance-backed.

4. Get three written quotes

Describe the same job to three companies and compare written quotes line by line. A proper quote lists the work, materials, start date, duration, payment stages and VAT. The form on any Hammerscore company page can request quotes from similar companies nearby.

5. Check the paperwork trail

The name on the quote, invoice and van should match the business you checked. Limited companies can be verified free on Companies House; sole traders should still give you a trading address and landline.

Red flags specific to this trade

Any one of these deserves a pause; two together mean look elsewhere.

  • a large deposit demanded before materials are on site
  • no written contract for a job worth thousands
  • a quote far below the others with no explanation

After the job

Pay by a method with a record, keep the paperwork, and leave an honest review — good or bad. It is the most useful thing you can do for the next person searching this company's name.

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