CHRYSLER JEEP saw prices soar during a closed sale at Manheim Coventry, which achieved a 100% conversion rate. All 92 vehicles sold at the event, attended by 51 dealers, which saw a 2000 W-reg Jeep Grand Cherokee push up its used book value by £1,500, making £26,300, compared to prices of £24,800 last year.

A spokesman for Chrysler Jeep, said: 'We are having a sales drive within the auction network to show to the valuation experts the prices that our cars can achieve. This method of showing how our vehicles are in demand will drive up residual values in the guides. We cut prices last year and even so our used values have been increasing.'

Tony Styles, an editor of CAP Black Book, said: 'It was a closed sale, and some of the dealers had already pre-sold vehicles, so they were able to pay strong money. However, residual values for the manufacturer's product are being marked up, with Voyager and Jeep Cherokee diesels up about £200.'