For example because you don't like how eBay is very popular and taxing you a lot on your sales, or taxing sellers a lot on your buys. Or because you have bad experiences with eBay or PayPal. Scammers for example. I can imagine tons of reasons, but none of them applies to you, because else you would not ask this question.

You can look around here what other people are asking and know how much you'll approx get for it. You can learn how to make a descriptive and honest auction (or sale / buy now) as well. On eBay you get additional build-in guarantees, while you don't have much information about many posters here without further research. On an advertisement/billboard you do NOT get any build-in guarantees, but you (usually) don't pay any 'tax' either. Same as here. You also have to make sure you reach as many potential buyers as possible. Putting it on eBay with a link from here _with_ accurate description here gives you the best of both worlds, I'd say.

Just put it on eBay. Sell it to the person who gives the most for it. Be clear, descriptive, honest (but don't write too much like I do), include S&H costs, be sure to think of international buyers.