If you need to change your car at the moment, you could be one of the few winners of the credit crunch.

Used car prices have been falling fast, and nowhere faster than at the auction halls, where unsold cars are starting to back up. Large cars have been particularly hit by the recent fuel price hikes. If you have the cash, there are some real bargains to be had. The car industry bible Glass's Guide wiped up to £750 off the value of many larger cars between May and June, and is predicting further falls as demand declines. British Car Auctions said this week that the value of ex-fleet/lease cars fell £214 in May alone.

BCA director Tony Gannon says: "This is not a seasonal price adjustment, but a more fundamental re-aligning of prices." He adds: "First-time entered and realistically valued stock is [selling] well. Re-entered vehicles, however, are struggling to get the buyer's attention unless there has been a sensible price adjustment."

Car auctions are not for the faint-hearted, and unless you have a strong knowledge of both cars and auctions, it is probably best to get some help. Joe Dowd is a professional buyer who will check the vehicle and bid on your behalf. Simply tell him what you want and he will do the rest. And because he pays trade commission, it won't cost much more than if you had bought it yourself. Go to auctioncarbuyer.co.uk.