IMO Ebay has its pluses and minuses.
Pluses: great chance to seek out unusual one off rare little items, no need to spend hours trailing the malls, much more stressfree shopping rather than battling with the crowds and being overwhelmed with all the mass of cheap stuff in the shops (can;t see the wood for the trees kinda thing). Also, it is possible sometimes to pick up bargains and get cheap little gems at far less than RRP.
Minuses: obvious ones like can;t check it fits first, colours in photos often turn out quite different in real life, a few fakes and bogus sellers out there. It's not marks and sparks so you can;t just return it the next day for a full refund.
All in all, i personally think the advantges of ebay far outway the disadvantages. Even if you do make a few mistakes, like it doesn;t quite fit afterall or something, then that is what ebay is all about and hopefully it was quite cheap in the first place or else you wouldn;t have risked it, and also the mistakes should be outweighed by the fab one off bargains you've managed to win over time. Besides, if it's that bad, you can always re sell it on ebay and sometimes get more back than you bought it for yourself!