Customs Ways to protect yourself in a long distance trade

If I had a car worth $30K I'd be tempted to sell it and buy two $7500 cars, a $7500 pickup, and a $7500 trailer......

No way should a trade of that value be done sight unseen. You already know that. I posted just to humor the group with my math skills.......

 

OK you have a friend look at the long distance car and he says it is good. You make the trade and send your title to your friend to give to the long distance owner. Your friend only gives the title if the deal goes through. That is the best I can figure if you can't do the deal yourself.