A:Buying or selling used outdoor equipment was once a major hassle. Other than yardsales, placing a classified ad was the only reliable way to trade used gear, and for smaller-ticker items the cost of the ad itself might easily eat up any profit. But—hurray—we now have the Internet. And everything is easier.
For years, I've been buying and selling bicycle gear on ebay. It's my go-to site for components and wheels, unless I can find on-sale parts at an online cycle shop like Excel Sports. But for general-purpose outdoor gear, like this Sierra Designs ASP 2 tent ($149 for buy-now, less than half the original retail price) ebay is probably your best bet.