You could get the VIN and run it through Carfax. It’ll cost you a small fee, but it should tell you the last registered owner. Does it have a tag? Get the number and call the DMV.
In some states/locales, there are restrictions on the sales of salvaged vehicles. There is a designation on the vehicle’s title. A pal bought a junkyard car as salvage and fixed it up pretty nice, but whe he wanted to sell it, he could only sell it to someone else that lived in the same county as where he salvaged it from. -And he salvaged it in a Missouri county, and was allowed to register it when he moved to Illinois, but when he sold it, it had to be to someone in the original Missouri county. So you might want to ask the DMV first about any possible restrictions…
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