Part 1

1 Clocked cars
This is the way dodgy sellers work: take a high-mileage car, wind the odometer back and, hey presto, its worth hundreds of pounds more.

Its relatively easy to alter a cars mileage using a computer and the right software, but its far harder to cover all the signs of a high mileage.

The cars general condition will give a pretty good indication of how hard a life it has led. The number of stone chips on the bonnet, the sagginess and wear of the drivers seat and the way the pedals are worn down are all giveaways.

Usually, the service history and MoT test paperwork will allow you to track how quickly a car has covered its miles. Some vehicle history checks also include any past mileage readings.

2 Stolen goods
By using bogus registration documents and fake vehicle identification number (VIN) plates, criminals can disguise stolen cars.

This can be as simple as slapping on a set of fake numberplates, or as complex as respraying the whole car and using fake VINs to carry off the scam. Once youve checked that the VIN on the V5C registration document and the history report matches all the VINs on the car (including stickers on door edges, the boot lid and the bonnet), phone the DVLA on 0870 241 1878 to check that the V5C itself is legitimate.

Be wary of anyone who seems to pressing for a quick, cheap sale. They could be hoping you wont look too carefully at the car as you rush to shake on the unbelievable deal.

3 Funny money
Get taken in by fake cheques and unpaid finance and youll end up with no car and no cash.

When selling a car, dont accept personal cheques and be wary of bankers drafts. Contrary to popular belief, bankers drafts can be forged, and you often wont find out until several days later when your bank discovers the deceit and takes the money back. By that time the buyer and your car will be long gone. Insist on an electronic bank-to-bank transfer that way youll know the cash is real and safely in your account.

When buying a car, always get a history check that shows if any finance is outstanding. If someone hasnt paid off a loan on the car youre buying, it could be repossessed and youll struggle to get your money back.