Start by selling your own extra stuff. Then, once you get a feel for selling your extra stuff, go door-to-door in nicer neighborhoods in your town. Develop an eye for what will sell and what won't (old laptops, for instance, could be a gold mine if you know how to format them to get rid of the previous owner's personal data.) Sign a contract where you take 25-30% (or more) of the gross sale. Your customers will be happy to get cash for their old junk, and you'll make some good money selling other people's stuff. eBay
