I used to work for an NYC based competitor to Tradesy and can tell you first hand that a good portion of the complaints on this site are not real. One of the owners (who will remain anonymous) of the company I used to work for is pissed for what he believes is Tradesy blatant ripoff of his websites format.
There are approximately four main websites that are exclusively in the fashion resell space. Three in the east coast and one in the west coast (tradesy). It is no accident that the other three do not have reviews on this site. The website I coded for had extremely shady practices and did in fact knowingly sell counterfeit product.
I am not going to say that Tradesy is saint of a company, but I believe they received a pretty raw deal!
Review about: Tradesy Website.