I have never had a problem with eBay either. I do tend to stick with in-country sellers and I usually buy from people with very high ratings. There are a ton of sellers with 98%+ ratings with over 10k reviews.
this is the key for me as well. Not only that they have high ratings but preferably with a lot of ratings. If it is 1000 or more you know that it isn't just them or friends rating them. And those people with high rating care about those high ratings and do what they can not to mess them up. Same applies to Amazon. The customer ratings is, IMO, the greatest advantage to online shopping.