Rather than ranting about all the Y's and where 4's, I suggest you talk to your insurance company as they were the one's who sold him the car, how else do you think he turned up on your door step, he has all the registration doc's for the car.
I used know a couple guys who brought insurance write off's. To look at them, they looked like they didn't have a pot to :tsktsk: in and they certainly were not the nicest people in world, walk in there workshop and it was like walking in other world, all the lastest equipment all brought and paid for and every job prefessionally done. Remeber never judge a person by there appearance are the way speak.
One other thing, All the Limos you see on road, they are all 'Cut and Shut', they all start out life as base car, then cut in half and all the bits added and then joined back together. Just because of few bad apples and there are some real :tsktsk:ing scum bags out there don't judge them all the same, he could just be guy trying to make a honest living, cos there is no law against repairing Write-Off's