I'm looking for a PHP e-commerce application which either has a buying feature either built-in, or as an extension. Preferably free, although I may consider something if it isn't too expensive.
My client needs a shopping cart where customers can sell or pawn pre-owned items at different quality levels. These items would already be in the stock database, which would then need to be updated automatically as a user sells them.
I may be able to code this myself if I find something close, but anything pre-made would save a lot of time as this is a very core requirement.