What is the best/worst you've done when selling at a swap meet?

Not exactly a swap meet, but I made out like a bandit on a 69 Barracuda parts car about 20 years ago. My 69 340 Barracuda had an automatic, but I always wanted a 4-speed. I checked with Brewer's, but it was going to be at least $2500 to buy what I needed. I found a 69 Barracuda FB with a running 340, 4 speed, bucket seats, console and an 8.75 with 3.55 Sure Grip on Ebay. I won the auction for $2700. It cost me about $400 to drive to Chicago, rent a trailer and drive it home. So I'm into it for $3100. I took out all the 4 speed stuff, then I parted the rest of the car out (it was pretty rough). I also sold the automatic and the console out of my car since I would not be needing it. I made about $3500 selling stuff. So I got the four speed conversion for better than free.
Well, in that case


I was looking for a daily one day, and I had my heart set on a 99-03 cougar

One showed up at a local lot, and I was on it like a hawk

The guy said he couldn't sell it to me untill his mechanic had gone through it, but once it hit the lot, he probably wanted 8 grand for it


So I show up a week later with 8 grand, and he was not happy
Turns out when the mechanic went through it he found it needed a new clutch (which meant dropping the drive train and lifting the body up before you can even get the transmission off the engine)

But he was a man of his word and sold it to me for the aforementioned 8k

I drove that car for a year or so before I totalled it (about a week after I spend 300 dollars on replacing the sunroof)

After my deduction the insurance wrote me a check for $9500

I quickly swapped out the sunroof and sold that for $750

Made out well on that car