Tennessee used to be the title wash hub for the Southeast. In the big Midwest floods of the 1990's a LOT of cars were retitled and sold at auction. I personally saw an Escort GT which still had about 1/4" of sand under the carpet. It had come from the auction with a Tenn title. That had a lot to do with why so many states tightened up on the whole title thing.
I just got the title to my XS here in SC. Basically, I filed a mechanic's lien against the bike (3 years' storage) the title company went to the magistrate and filed my claim, the magistrate's office notified the last owner and gave him 30 days to retreive the bike (to do so he would have to pay my lien) and after the 30 days was up the bike was auctioned and awarded to me for the storage fees. I got a magistrate's sale letter which I then took to the Highway Dept and traded for a real live title in my name. It cost me $135, I probably could have done it myself but it takes a fair amount of time to do all that so I paid him instead.
So what you can do is buy the car from this guy, get a bill of sale, move it to your property and start charging, say, $10 a day storage. Don't forget to add in your towing costs! Let it build up for 3-4 months then go after the title through the State of Washington.