The buyer may purchase gear which is stolen or simply doesn't work. Unfortunately, there is no way to know if it is stolen, and no way of testing the gear at these meets. The technology of ham radio, radar detectors, and other similar equipment changes rapidly, and the consumer may be purchasing pretty but totally unusable boxes. Our California store suffered a break-in several years ago. Soon after, I found my personal hand-held ham radio for sale at a local swap meet.
Flea markets are a fast way for thieves to sell their ill-gotten goods.
The receiptless culprit was arrested, but claimed he purchased the radio from another person, who was unknown, of course. I have a number of friends who go to swap meets. They are bright and knowledgeable people, and usually do well in these ventures because they confine their buying to equipment they know and can test. Recommendations When purchasing electronic gear at a swap meet, make sure you've done your research. Know what you are looking for technically, and make certain you view the seller's current business license and resellers permit so that you have some recourse.