If your supplier gives you special discounts or prices based on how much are you ordering, you have the ability to set up the Tier Quantity in ERPAG.
When you create a supplier's price list, just set up the same item as many times needed and add different number in the Tier Quantity field.
When you generate the purchase order for the assigned product, from a select supplier, the price will automatically change when you change the quantity:
Even if you have Sales Order for a certain quantity that's entered in the Tier quantity in the supplier's price list:
The system will display you the corresponding price from the Tier quantity in the Fulfillment list: