This is a common situation - you see the airplane you want, it is listed at a price that seems reasonable, and it is located 1000 miles away. Both the seller and buyer know enough the other can't be trusted (initially) (completely). As the OP and responders have noted, there are risks for both parties. Several responders have noted what the buyer can do to mitigate some of those risks. Skilled negotiators recognize not only their risks, costs, wants, needs, etc, but also the other parties risks, costs, wants, needs, etc. The negotiation is about a whole lot more than just price. (In fact, I will not sell to a buyer whose first question is on the selling price.) The negotiation is about problem solving in a way that is mutually satisfying to both parties. Lot's of value is lost by parties who won't or can't do that.