Each stock code in Atrex has a list, sale, and 5 discount prices. These prices can be either set manually or they can be automatically calculated based upon the cost of the item.
If you have a set of inventory items that you want to have the same pricing options, you can set up a pricing category and associate those items with the desired price category. Then if the pricing structure for those items change, you can make the change in one place and automatically update all of the associated items.