nothing can be sold. You recycle - for free - something you don't want to someone else who can use it. Or, you ask for something that you want that someone else has and no longer needs/wants.
You have to be a registered member - each area has a group of moderators to control activity. I've given away quite a few things on Freecycle - both in New Orleans and in Houston.
Just google "freecycle" and your home town. It's very interesting sometimes just to read what folks are asking for or offering.
Whenever I utter the word "exercise" I will rinse my mouth with chocolate!