How to spot a cowboy builder — and avoid getting stung (2026)

Red flags before the work even starts

The most reliable warning sign is pressure. A tradesperson who turns up, quotes on the spot, and tells you the price is only good today is giving you a reason to skip the due diligence they don't want you to do. Reputable tradespeople are busy — they don't need to hustle you into signing on the doorstep. Walk away from anyone who rushes you.

Cash-only and no VAT receipt should make you very uncomfortable on anything above a small job. It is not illegal for a sole trader to work off the books below the VAT threshold, but on a job worth £2,000 or more, a legitimate trader should have no objection to giving you a written quote, a proper invoice, and a paper trail. If they resist, that is the answer.

No fixed address, no landline, and a van with magnetic sign panels are not on their own damning — plenty of sole traders operate that way — but take them seriously when combined with anything else on this list. Ask for a company or trading name you can look up, and then actually look it up on Companies House or check whether they appear anywhere beyond their own website.

How to check a tradesperson properly

Start with reviews, but read them critically. A profile with forty five-star reviews posted over three weeks, all using similar phrasing, is less reassuring than a profile with twelve reviews spread over two years including one mixed one. Look for specifics — a review that names the job, mentions a small problem that was sorted out, and sounds like a real person is worth more than a string of 'great guy, would recommend.'

For certain trades, membership of a recognised scheme is genuinely meaningful. Gas engineers must be on the Gas Safe Register by law — you can check a registration number at gassaferegister.co.uk and you should always do so. NICEIC or NAPIT registration matters for electricians. For builders doing structural or drainage work, Trustmark membership is worth something, as members agree to a code of conduct with a complaints process behind it.

Ask for references from recent jobs within the last twelve months, and follow them up. Most homeowners never do, which is exactly why cowboys get away with it for so long. A two-minute phone call to someone whose kitchen was refitted six months ago will tell you more than any marketing material. If a tradesperson hesitates to provide references, that hesitation is itself useful information.

Protecting your money once you hire someone

Get everything in writing before any work starts. A written quote — not an estimate — should specify the scope of work, the materials to be used, the timeline, and the total price including VAT. If there is any possibility of additional costs (for instance, if opening up a wall might reveal extra work), the quote should explain what triggers extras and how they will be priced. Verbal agreements are almost worthless if a dispute ends up in the small claims court.

Be very cautious about large upfront deposits. For most domestic jobs in the East Midlands, a 10 to 20 per cent deposit to cover materials is reasonable on a job worth £1,000 to £5,000. Anything above a third of the total cost paid before work begins is a warning sign. Stage payments tied to completed milestones — first fix done, second fix done, snagging signed off — protect you far better than paying in two lump sums. Never pay the final amount until you are genuinely satisfied with the work.

If you want a straightforward way to find tradespeople who have already been through a verification process, posting the job on Rank My Builder puts it in front of verified local trades with reviews you can actually check — and jobs are capped at five quotes, so you won't be bombarded with cold calls from people you've never heard of.

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