It would be really useful to add an option to combine listings that take different quantities from the same pool of inventory. As in to combine a 1 pack and a 3 pack of the same product so they take 1 and 3 from the inventory respectively when they're sold. As it is currently, when selling a 3 pack of something it takes 1 from the inventory and then either the other 2 have to be removed manually or alternatively don't combine the listings at all and keep track of 1 and 3 packs of inventory as separate inventory items which means a lot of manual correction and inaccuracy.