I loooooove eBay. I also hate eBay. I love it because I've been able to turn over so much of my handbags, shoes, various pieces of expensive clothing, and parlay them into what is now my Raisin Birkin. There's also the money I pulled in from those sales for our wedding and reception. So being an honest person (and not a cheat) makes eBay a good thing. But then I hate eBay, because I've been cheated before. I had to give up my eBay id because a buyer made a fraudulent claim that she didn't receive a handbag I sent her with signature confirmation. The loophole was that it wasn't sent with ONLINE signature confirmation, so my PayPal denied the claim, SHE got the money, and SHE got the handbag. They only got %50 of the funds, but no way in hell was I going to allow them to get the rest. </rant>
As for buying from eBay, I'm very, very picky now. I was burned once (for $300 which I never got back), for buying a very well-made fake LV pochette in 2002, back when I didn't know the difference between fake and real (info was not as readily available). But I have since heavily educated myself and invested significant money and time, and I have been very fortunate to have my select, tried-and-true sellers that I've always gone to. I'm lucky they transitioned from selling LV to Hermes, too! I generally look for the MPRS rating, since those sellers extend their personal pride in being a responsible seller from LV goods to Hermes goods. I hope I'm not breaking any forum rules by writing this -- let me know, and I'll edit appropriately.
I'd say I've done about 500 transactions of purchase and selling on eBay, and have been burned about 5 times. That's enough to be aggressive both as a buyer and seller, because losing money just plain sucks durian.
In my opinion, if you decide to hang out on eBay, get to know the system, decide what boundaries to set for yourself, and read all the fine print.