An inventory was a list of a business's material assets.
In 2370, Rom was completing the weekly stock inventory for Quark's. Quark came to pick up a misbehaving Nog from Deep Space 9's security office in his stead, explaining that he didn't want to interrupt his brother, as Rom was easily distracted and might lose count of the items he was inventorying. (DS9: "Sanctuary")
In 2372, Quark, incredulous at Hanok's claims at the Karemma's honest business practices, questioned whether he had ever padded an inventory (claimed he had more items than he did). Hanok continued to deny he ever had. (DS9: "Starship Down")