I've got the ecommerce experience working so you can buy cardboard.
Right now, I'm building a easy process to allow customers to sell, consign and at a later stage trade cards. You may have noticed there is a Card market page already and an inventory cart. This is still a work in progress as there's a bunch of backend stuff I need to build out while the frontend UI should give you a sense how you as a customer can sell and consign cards to me.
If you're one of the rare person that wants to me sell me cards at (70-75% market) or consign me cards before this feature is available, just drop me a email.