Even if a used car looks good and drives well, it could be a write-off, stolen or have outstanding finance. Unless you're buying from a dealer who can show you a data check, you should do your own check before sealing the deal.

Leading data check agencies HPI Equifax and Experian hold huge databases, accessed via the HPI Check, the AA and RAC, and various independent data check services.

Costs are around £40 per check, depending on whether you require 'extras' such as mileage verification and valuation. Services are telephone-based, with confirmation in writing. You need the car's registration number, its 17-character VIN (Vehicle Identification Number) and your credit card.