A friend of mine has sold her panties online before, taking special requests and including a photo of herself in them. She enjoyed it for a while, made a fair bit of money, but eventually found doing all the postage and admin stuff too time consuming and boring.
I sometimes buy panties but only if she removes them in front of me. Bras too. Years ago we did a game on the beach in front of a fire where we had a contest to see which people could trade bikinis and bathing suits the fastest. Obviously, the idea was to see everyone else naked but it was fun to see people try to fit into clothing that wasn't quite their size. It was actually more difficult for us guys since most of us had a partial or full erection so when the trunks came off, it was all on display. Fun times.