Why the paranoia? The odds of finding Sumdood renting a table at a gun show to move his hot guns are pretty small. And if you confine you purchases from private sellers (are you even allowed to do that in Taxas?) to locations that generally do not involve open trunk lids* you should be OK.
*There was this time I sold multiple guns to a friend and we exchanged cash with all the cases piled on the tailgate. Took place in public in a parking lot of the place we had met for breakfast before the sale was completed. With cops standing around watching us. And nobody fainted, nobody drew down on anybody else, and nobody got arrested. And yes, I've got witnesses (they all wanted to fingerfiddle the goodies).