i would say this is your car mate and you should get it back if not the trader should give you your money back, if he can get the car back of you he should give you your money back, you did say the first time that you did a hpi report on it and that it was o.k, get back in touch with who did the report for you and see if thay will send a copy to you so you can take the matter further with your solicitor.

good luck