ebay is fine, for those who by and sell in moderation.
some can even make a living. however, it is not a guaranteed paycheck, so i would not invest such time and thoughts into such an endeavor.
my experience with ebay has been a twisted turning-around road. sometimes, i had to deal with scammers, or for my laptop that i still have, which was listed three times, and all bids went $500+, i knew they were scammers. so, i elected to keep my laptop. however, buying can be a little scammerish as well. i purchased a roll of "unsearched" wheat pennies. upon arrival, there were more than 50 pennies, and they were opened - also known as "searched"... so, i communicated with the seller, since in the package, he had wrote "no returns for opened items" which was not part of the auction terms, and we threw conditions at each other, until we decided the best route was to chalk it up, and move on. both got positive feedback, but i decided not to use ebay for that.
however, i still use it, under a different alias now, because i just "won" a best-offer deal, so that now i can put wireless on my laptop (the one noted above), which was purchased off of ebay, as well as the ram upgrade for it, and also have bluetooth, so that i can download the pictures from my phone to the computer.
reality is, as long as you are cautious and diligent, you will be fine on ebay.
remember: guns do not kill people, it is just a tool. ebay is the same way.