Buying a used car can be fraught with danger as unscrupulous sellers attempt to pass off cars with a lower mileage than they have actually travelled.
As a result, HPI has called on motorists to sign a petition to stop people illegally altering the mileage on cars.
Phil Peace commercial operations director for HPI explained that while "clocking itself isn't illegal … selling a 'clocked' car without declaring its true mileage is".
Mr Peace said that Trading Standards has estimated there are 50 firms who are changing mileages.
"A lower mileage can add hundreds or even thousands of pounds to the perceived value of a vehicle, so buyers have a lot to lose"
This could result in consumers paying over the odds for a car which may require servicing and repairs sooner than they would expect.
The Office of Fair Trading suggests that consumers may be overpaying for vehicles with altered mileage to the value of £580 million annually.
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