On my current cash register, for items that haven't been entered yet into inventory, I can do the following:
enter price... press a product category key and the amount is added to the purchase total. i continue entering prices followed by a category key and it all adds up at the end. this is how i track which product categories are doing the best in our shop.
i know i can assign an actual product to a quick key, but i just want to add a category so that i can use the POS *while* i'm gradually transitioning all of the stock into inventory.