I too have purchased used tow bars off ebay and Craigslist. One thing that ebay has that C/L doesn't is seller ratings. Ebay is a bit pinache about bad seller ratings on their program. So, if you're going to sell on ebay, you better be honest about your ad. If there's a problem with the product your trying to sell, you better LIST THAT PROBLEM so that it's out in the open and, any potential buyers KNOW WAY IN ADVANCE that your product is not perfect.
So, if your product IS perfect and there are no defects, than if you see it listed that way, it more than likely is perfect. All you have to do for ebay that is, is check the sellers ratings and scores. Our last purchase, a Blue Ox Alladin, was way less than 1/2 price of a new one and, had way gear with it than you'd get when purchasing new, all for one ultra low price.
It's been a great tow bar with no issues what so ever.
Scott
Scott and Karla SDFD RETIRED2004 Itasca Horizon, 36GD Slate Blue 330 CAT
2011 GMC Sierra 1500 Ext Cab 4x4 Toad
2008 Caliente Red LVL II GL 1800 Goldwing KI60ND