You havent used bazaar.tf much have you?

A lot of trades end up having to span far more trades than they need to to get everything posted. Why not give your users the ability to post everything they are willing to trade in one listing. I have a trade up for 8 of the 20 hats I want to sell off, and its not really the best way to list everything. A lot of trades have more on the plate than just those 8 items anyway.

it wont let me put up more than 8 items on the offering side.