I prefer cl or estate sales. Some machines that I would have considered strongly I've walked away from seeing their true condition. A trick on Ebay they use is to show the good condition side of the machine, deceptively leaving damage obscure in the pictures... Then you have to pray it is packed properly and not abused. I insist on Fedex or UPS case the USPS specializes in doing a poor job on this sort of stuff.
Your mileage may vary.