At smaller shows and race track shows, you should look for the vendors who didn’t come in a professional looking van. You want unprofessional looking venders. I avoid venders that only have rare, clean, high dollar items. They know what they have. I like the guy selling from the tail gate of his truck who looks like he just cleaned out his garage for extra cash. This guy’s parts are dirty and unorganized. Possibly, his wife is there to help him sell. I also look for the seller that doesn’t look like a “car dude”. He could be the son, who is cleaning up his “poor old dead dad’s” car parts so the family can auction off the house. This guy usually doesn’t have a clue.
Tip: look for high dollar cosmetic items like mag wheels, consoles, etc. that are dirty. If the seller didn’t take the time to clean the item, they may not be aware of its value.
This snippet of information is direct from Dave’s book “Classic American Car Parts” get more great part picking information like this and learn to run an eBay business selling classic car parts by buying the book today.