Citizens Advice reports that complaints about second-hand cars bought from independent dealers are the most common complaint on its Advice helpline.

The service, which started in April, received 150,000 calls in its first three months on all subjects, of which 12,000 calls were about used cars from dealers. Approximately 75 per cent of all car-sales complaints were about independent dealers, rather than official franchised dealers or private sellers (although we can't see what Citizens Advice could do about a private seller, unless it was a trader pretending to be a private seller).

The value of the disputed cars was £55 million. Citizens Advice chief executive Gillian Guy said: "If you're not a motor head, stepping onto a used car dealer's forecourt can feel like entering a lion's den."

"But there are things consumers can do to protect themselves, like looking out for unusually low mileage on an old car, which could mean it's been tampered with."

In response, Chris Mason, managing director of Motor Codes, which operates an Office of Fair Trading approved code of practice said "Despite the vast majority of garages and car retailers upholding the very best service standards, these figures are impossible to gloss over and demonstrate why some consumers are nervous about buying used cars. One of the most important pieces of advice offered by Citizens Advice is to find a reliable retailer, to seek recommendation and to find a seller that operates to an existing motor industry code of practice."