A large number of independent used car retailers are running dangerously low on good stock, meaning they are struggling to replace sold cars.
Research by car information experts CAP has revealed that motorists with good cars to part-exchange will get top prices from independent dealers, who are just as determined to buy retail-quality stock as they are to sell the cars already on the forecourt.
CAP asked more than 100 independent dealers to describe their current stock levels and whether they were having difficulty sourcing the right cars to satisfy demand.
The results demonstrated that independents have been struggling to keep up with demand for retail stock.
Mike Hind, of CAP, said: "Motorists who assume they will automatically do better by selling their car privately are behind the times.
"For independent used car specialists doing their best to keep up with demand, a good part-exchange is like gold dust in today's market.
"If they know they can generate another profitable future sale from your part-exchange, you can expect to be pleasantly surprised by how favourably a good independent used car specialist stacks the deal."
Nor is the problem likely to ease any time soon, with 89% of CAP's dealer panel anticipating no let-up in demand for used cars over the coming months.