To Ebay or not to Ebay ?

I love a bargain which is just as well considering the price of designer clothes.  I have recently discovered the joys of Ebay.  Yes, I am sure most of you have been there and done that but you really can pick up a bargain.  I recently purchased a Bonpoint cardigan and blouse which were in lovely condition. £10 each!  Bargain.  
I do wonder though if some people do their homework.  I have seen some Bonpoint items going for little less than what they sell for in the sale.  I'd definitely rather have a brand new item, packaged beautifully from the store than from who knows where.  For now I tread lightly and keep an eye out for a gem.  They are out there!