How to spot a dodgy builder?

A dodgy builder shows himself in behaviour before he shows himself in brickwork. The classic tells: a large cash sum demanded up front 'for materials', nothing offered in writing, and answers that slide sideways whenever you ask a direct question about insurance, address or past jobs.

Watch how they arrive. Rogue traders knock on doors ('we were working up the road and noticed your roof'), quote on the spot, and press you to decide today because the price 'only stands this week'. A genuine firm has more work than time and never needs to pressure anyone. Be equally wary of the quote that comes in far below everyone else's. That gap is not efficiency; it is missing scope, missing insurance, or a plan to hold the job hostage with extras once your kitchen is in pieces.

The vanishing act follows a pattern we know well from taking over abandoned jobs across South East London. A strong first week, then shrinking hours, then a van that stops appearing, usually just after a payment cleared. Mobile-only contact and no fixed business address make that disappearance easy. Ask for a registered company, a yard or office address, and two past clients you can phone. A straight builder hands all of that over without blinking; we tell people to demand it from us too. The paperwork side, contracts and deposits and warranties, is a separate list of red flags in its own right.