Ubercart

I have a rather unusual request. I am looking for a way for consignors to enter their own products with attributes and stock values. This seems to be no biggy. I can create each one of them a user account with certain roles/permissions to do just that. My main concern is that the admin of the site, or someone with that type of role needs to be able to use a barcode scanner once the purchase has been made with cash to remove the number of items in stock. I am not necessarily needing a point of sale from ubercart, but a way for them to be able to remove the item from stock with the automagic barcode scanner. I will also be able to talk the client into maybe changing her system in some ways so any suggestions might work. Thanks