NEW car buyers could pocket more than £587million this month just by haggling over the price of 55-plate vehicles, according to What Car? magazine.

The magazine has produced a list of 'Golden Rules of Car Buying' to help people searching for a new car to get the best deal.

The first rule urges people not to pay more than the target price - based on research by the magazine - for a new vehicle. The target price is a realistic discount figure for every new car on sale.

David Motton, editor of What Car?, said: "If every new car sold during the plate-change month is sold at target price, that makes a total saving of more than £587million."

Mr Motton also advises new car buyers not to give up on haggling, even on a vehicle already part of a special offer.

Salesmen may try to persuade you that a cashback deal or an interest-free finance package puts an end to price negotiation.

Mr Motton said: "These buying incentives are almost always paid for by the manufacturer, so the dealer still has a profit margin to play with. You can and should keep on haggling."

If you are being offered a part-exchange deal on your old car, make sure that a good price on the 55-plate vehicle is not masking and under-valuing of your current car.

And bear in mind that it is a buyer's market, so be prepared to walk away if you can't get the price deal you want.

Mr Motton said: "The salesman needs you more than you need them. There are plenty of other dealers ready to cut the price if your local dealer won’t."

Finally, people should guard against getting a good price on a new car but then throwing away the saving by not shopping around for finance.

High street and itnernet lenders are offering loan rates of around £5.8 per cent, while standard-rate dealer finance often charges interest at 10 per cent APR or more.

Mr Motton added: "Don’t assume the finance a dealer offers is competitive. Sign up to the first deal put in front of you and you could pay thousands of pounds over the odds."