My experience is that I never know where something will sell:
Lately, I've been using this forum, craigslist, and even letgo (free sales over the smart phone). Sometimes stuff sells and sometimes it doesn't. If I can't sell it fee free, I'll then list is on eBay.
I have had a few items languish for sale for a month, and then take the item off the market, relist it six months later to have it sell almost immediately!
Jim