The experts are warning that as the total number of cars on the road hits 31.4 million - as many as 10.4 million of them could have a hidden history. One in three are on the 'at risk' list - with one particular type of danger at record levels.
So what are the three most common types of hidden history, and how can you check a car before you buy?
Outstanding financeThe biggest type of threat in the second-hand car market is whether the person selling it has made all their car payments and owns it outright. According to the experts at HPI, many people don't realise that the debt stays with the vehicle.
If the debt remains unpaid, it will leave the new owner at risk of losing the car and the money they paid for it, if the finance company decides to reclaim the vehicle. The company says that one in four of the cars it checks for customers have outstanding finance, which means there could be as many as 7.8 million cars on the road in this position.
Change of identityThere are a number of things fraudsters can do to hide the identity of a car. This could include changing the number plate or obscuring the vehicle's chassis number (VIN). This is likely to be a step they have taken to hide a car that has been written-off or stolen.
MileageApparently 5 in 100 cars checked with HPI have a mileage discrepancy, which could equate to over 1,500,000 cars on the UK roads. Dodgy sellers use clocking as an easy way to increase the price of their vehicle. However, it also raises a number of risks. Not knowing the true mileage could also mean there's a risk of missing critical maintenance tasks, such as full servicing.
How do you check?All three of these risks will be picked up by an authorised dealer, who should be able to provide you with the paperwork to prove they have done so. If they haven't made the checks, or if you are buying the car privately, then it's well worth checking yourself with a third party firm, such as HPI Check or AutoCheck from Experian.
They all differ slightly, but will confirm whether the car has been stolen or written off. It will also give all the correct vehicle details, number of previous owners, correct mileage, and whether there is any outstanding finance. They will also ensure that the registration matches the VIN, to be clear that the car has not changed its identity to hide a murky past.
The providers also keep databases of cars that are being hunted down by finance companies, insurers and others for one reason or another (none of them good). Your car will be checked to ensure it isn't on the run from anyone.
A check will cost about £20, which is a drop in the ocean compared to what you could lose out if you find out further down the line that you are driving a car illegally - or one that is still owned by the car financing company.
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