If you buy from a dealer - and that applies to plush showrooms down to individuals who deal from home - you have rights under the Sale & Supply of Goods Act 1979.

These are that the car must be of satisfactory quality (bearing in mind its age), must be as described, and must be fit for its purpose. This means that it should be free from defects other than any you've been told about, should be exactly what you've been told it is, and should do what you might reasonably expect of it, including any particular purpose you have specified to the seller.

If you feel your purchase does not meet one of these requirements, you have a short period after buying it in which you may be able to reject it completely. To do this, you must stop using the car immediately and contact the dealer. Then you must follow your complaint up in writing and give evidence for any problems, including to any finance company you have used to fund your purchase. You will need to get an independent assessment of the car and possibly, if the rejection is disputed, take legal action to recoup your money.

If in a dispute with a dealer, you should also check whether they belong to any trade associations, what their policies are and whether the dealer is abiding by them. Also consider involving the Trading Standards department of your local council.

If you need to take legal action, you can make claims up to £5,000 in value using the small claims courts. Above this, you may need to employ proper legal representation for full court proceedings.

Alternatively, the dealer may offer to repair or replace the car. If you choose a repair, ensure the dealer provides you with a courtesy or hire car, or pays your travel costs while the repairs are being made.

Your rights when buying privately are much more limited. This is why some small dealers will try to pass themselves off as private sellers. Legal comeback is only possible if the car doesn't match the description the seller has given. So keep a copy of the advert and take it with you when viewing. Knowing where the seller lives is also important here, so make sure you are viewing the car at their home rather than a car park or motorway service station.

But even if you find the car has been wrongly described after you have bought it, proving the seller knew something serious was wrong with the car when they sold it to you is very difficult indeed.

buying a used car: useful links >>