Almost half of drivers who have bought a used car privately believe they were deceived by the seller, leading to a claim the practice is akin to "motoring roulette".

Of the 45% of drivers who feel they have been misled, more than two thirds (67%) think they were sold a faulty car and 21% think they paid too much, a survey of 2,300 motorists for the RAC found.

Some two in five used cars - or 2.7 million each year - are sold privately, according to figures from British Car Auctions (BCA).

Half of those surveyed (50%) said they bought privately to get the best value for money, but the RAC said the study suggested that confidence in making such an important purchase was being undermined.

Drivers' top three concerns about buying a car privately are existing mechanical faults (29%), purchasing a stolen vehicle (24%) and choosing a car that has been written off (13%).

Other common concerns include buying a car that is still being paid for on finance by someone else, higher maintenance costs than expected and the vehicle being worth less than its price.

Almost half of buyers (43%) spend more than 10 hours researching their purchase and a third (34%) invite a friend or family member to help them inspect the vehicle.

More than a third (35%) rely on a friend with motoring knowledge to help make the final decision.

RAC data services managing director Robert Diamond said: "Buying a car privately can work out cheaper than going through a dealer and is therefore a popular choice in the UK.

"But clearly many drivers don't have a lot of trust either in the person they're buying from, or in the car they end up driving away with.

"Sadly, motorists are telling us that buying a car privately appears to resemble something akin to motoring roulette.

"What's more, buying privately doesn't afford the same levels of consumer protection as buying through a dealership - putting more pressure on making the right purchase of a vehicle.

"Happily, this doesn't need to be the case and there are now a range of services available to help ensure that private buyers needn't spend hours researching their next car only to be let down at the very end."

The RAC has launched the Car Passport that allows buyers online access to information about their next vehicle, including a valuation to verify the seller is charging a fair price, information on a car's history such as common reasons for that particular make, model and year of car to break down and symptoms to look out for in a test drive.

:: The RAC surveyed 2,300 members of its Opinion Panel between September 23-30.

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