The right price for your car is a balance between its 'book' value and what will ensure it gets the attention of potential buyers amongst similar cars for sale.

Get this balance wrong and either you'll be deluged in buyers and end up out of pocket. Or there'll be a stoney silence and the cost of advertising will have been wasted.

Start by looking up your car in magazines like Parkers Used Car Price Guide or in the back of several other car magazines. You can get values for recent cars free on the Parkers and What Car? websites. On the Parkers site, for a small fee you can get a more precise valuation by giving any special features of your car. Car dealers use a different publication to find prices called Glass's Guide - for a small charge you can use this too.

KwikTip: always get a car insurance quote from Direct Line too,
as they don't take part in the price comparison websites.

But remember these are all only guides. If selling your car privately, the marketplace is an even more important indicator of the price you can set. So also look at the ads in your local paper or Auto Trader magazine to see how many cars like yours are up for sale, and their prices.

If part-exchanging your car, dealers won't necessarily accept the 'trade' prices the guides give as definitive. What they offer you will also be based on factors like whether they want your old car, what they think they'll get back for it when selling it on, the price of the car you're intending to buy and your haggling skills. Certainly don't expect a dealer to give you the sort of prices shown on their forecourt for similar cars to yours. Dealers have overheads to pay, they will probably have to spend money on the car to prepare it for sale, and you aren't offering them any warranty.

As well as its age and type, your car's value will be affected by its condition, mileage and any extras it has. Guides break down values by condition; usually Excellent, Good and Poor. When selling privately, if your car is in a typical condition for its age with no obvious faults or damage, then that would be classed as 'Good'. To achieve the 'Excellent' price, a car would need to have a full dealer service history, as well as being in a largely unmarked condition.

Average mileage is 10,000 miles a year. If your car is above or below that for its age, you can adjust the price accordingly. If the marketplace will allow it, factor in around £30 - £50 per 1,000 miles for a typical car.

Very few 'optional extras' add much value to a car. Those that do are an auto or semi-auto gearbox, leather seats, air conditioning and fitted satnav. Power steering and electric kit are found in most modern cars these days, so make little difference to price. Metallic paint and alloys, despite also being increasingly common, are worth a little extra simply because they add appeal and make a car easier to sell. And a sunroof is always a plus. If a prestige car doesn't have all these sort of extras, that can greatly reduce its appeal and so have a serious negative impact on its value.

Taking all this into account, work out what a private buyer or dealer is likely to be willing to pay and, if you can, add 10% to allow for a bit of haggling. But also decide what's the absolute minimum that you'd accept.

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