Add / Delete Inventory API Endpoints?

API Question from someone used to programming Amazon and Discog API’s, and a newbie with TCGPlayer: is there an endpoint for posting and removing inventory? I thought the “Create ProductList” endpoint would be the place, but the documentation is really weird. The documentation specifies a “data” element that includes condition and quantity, but no productid’s. How does that work? And even if we got that endpoint to work, does a human still have to fuss with it for the inventory to go live?

Basically if we buy a card in the store, we want our software to auto-add it to TCGPlayer, and if we sell a card in the store, we want our software to auto-remove it. I’m not seeing any endpoints that fit either bill exactly.

Can someone point us in the right direction? Thanks!