Green flags

Diagnoses before quoting; agrees a fixed price before work starts; explains the parts choice and cost; is happy to show you the old parts; and offers a warranty on the work. A clear, itemised idea of what’s being done and why is the biggest sign you’re in good hands.

Red flags

A big-money diagnosis without a proper inspection; vague pricing that grows once work starts; refusing to explain what’s being replaced; and pressure to do lots of unrelated work at once. Those are the moments to get a second opinion.