What can a buyer do to prevent wasting time buying a non-existant vehicle

Dealers are smucks. All you can do is deal with the best dealers you can find. Most new car dealers have a reputation to uphold but used cars dealers have no reputation at all. Check online reviews but take them with a grain of salt.

Flying in to buy a common truck like a Tacoma is nuts. You won't save anything and cheap prices will usually mean the truck is a POS or it has fake pricing. Buy locally unless you live in the rust zone.

Unless you're looking at an unusual or collectable vehicle, buy locally. Any money you save on the purchase of a typical vehicle will be eaten up by the airline ticket to fly out to get the vehicle. Then you have to factor in the cost of gas, tolls, food, and hotel for the return trip. Hope that helps! Jim