I found some great deals on my area Craigslist, though I never did buy. The problem with buying used from far away and sight-unseen, is that you don't know how worn out the equipment is, and the shipping is very expensive between two private parties.
Once in a while, a hitch & trailer company, or RV dealership will clear out such excess equipment, often brand-new but with damaged packaging or without the original packaging. I bought a new Roadmaster tow bar kit for our Jeep Liberty, and a "Unified" brake controller kit from such places on Ebay. Prices were 66% (2/3 off) typical retailer prices. The Roadmaster kit was missing some hardware of which Roadmaster quickly provided what I needed. The brake controller came with everything, but I called US Gear in advance before purchasing to make sure they backed up an open-box purchase, of which they did.
In my two cases, everything came in perfect condition. Nothing scratched, beat-up, weathered, or otherwise less than new-condition. Installing everything myself saved piles more money.
