Stolen motors
One thing no-one has mentioned is stolen cars, there are a lot of cars being stolen in the EU and US and then shipped here. It pays to do a US/EU HPI on any import (do this from chassis numbers) it can turn up some real frights.
If you buy a stolen car do not expect to be able to keep it, several have been caught by this over the years, the garage or individual does not appear to have to refund the buyer despite selling stolen property and the police confiscate the car.