Prior to February average values had risen for three months in a row.

Average age of vans sold at Manheim’s auctions in April increased by one month to 53 months but average mileage was down by 1168 to 75,095 miles.

Year-on-year, average values have slumped 12.8% (down £564 compared to April 2010), average age is one month lower and mileage is up by 2061 miles.

Manheim said car-derived vans fell in value by 2.3% to £2709 in April, small panel vans slipped back by a marginal 1.3% to £3984, medium vans plummeted by 7.1% to £3612 and large vans fell by 4.5% to £3871.

Manheim’s CV boss James Davis said that while sold volumes in each month of the first quarter of the year had risen by between 20% and 35% year-on-year, in April this figure had dipped to 16% – partly due to the extended holiday period hitting retail activity and putting pressure on conversion rates.

“This hardening of the market is leading traders to change their buying patterns,” he said. “Instead of stocking a £10,000 van they are focusing on lower price vans that may sell more quickly and are avoiding damaged vehicles that need too much work or too much time to repair.”

Tim Spencer, group CV auctioneer, warned buyers of late-year, low mileage vans to expect a tough few months.

“Decent volumes of these vehicles are just not out there at the moment and the few we do see are being fought over so furiously that the final price achieved leaves little room for good profit on the forecourt.”