Research has highlighted the dangers of selling cars privately, warning sellers that thieves can pose as potential buyers.
According to Tracker stolen vehicle recovery specialist, private car sellers should be careful when advertising their car and inviting buyers to their home.
Car owners are being reminded to keep their keys safe at all times, after figures showed that £15.8 million worth of vehicles reported to Tracker last year were illegally taken using the owner's keys.
BMW X5s, Range Rovers and Audi RS4s were named among the most frequently stolen and recovered vehicles of 2010. This emphasises the importance of having a comprehensivecar insurance policy.
Stuart Chapman, police relationships manager of Tracker, said: "In 2010, the number of car thefts involving keys rose to 84%, compared to 74% in 2008, confirming just how vulnerable car owners truly are to the chances of home burglary or assault from car thieves.
"Today's in-car security systems make it difficult for criminals which means they are turning to more sophisticated methods. Whilst stealing a car as a result of a classified advert in Auto Trader is thankfully pretty rare, car thieves are regularly breaking into homes to steal keys and, as this case proves, many resort to taking keys from owners by force."
He added: "We advise car sellers to take sensible precautions when advertising their vehicle. Prospective buyers are still strangers and may not be the genuine article, so people should think twice before inviting them inside."
"We advise car owners to look after the security of their keys, keeping them out of sight, rather than leaving them on the hall table or a hook by the door."
Copyright © Press Association 2011