Had the same thing a couple years ago...nobody wanted it after listing on craigslist & ebay. Eventually ended up at the swap meet and nobody wanted it so it stayed in the trash can when I left.
You never regret buying something at a swap meet, but sometimes the things you don't buy will haunt you for the rest of your life.
I always have the oposite problem, I come home from swaps with total***** I got for a song and a dance. Parts to cars I never will or have owned.
I am like that also,I have to over think about it until its too late.I can't count the things I regret passing up.A week or so ago I bought a transmission I had no use for because it was a good deal.Now I am happy I got it because I have decided to use it in my truck.Like Kiwi Kev said,you only regret what you pass up.You can always resell what you don't use.