Accounting question

My question is concerning when and where to account for terms as it relates to our cost of goods sold. Right now our POS/inventory software is completely seperate from our books(quickbooks). The problem we have is tryign to correctly calculate the value of our inventory and coming out with a correct cost of goods sold. We are probably going to start reflecting the price we pay, including the terms, in the price of the inventory rather than make an adjustment after the fact to the books. The problem with this is that when I create POs I like the price to match what the vendor shows as price. This is always before discount. It creates an extra step where I have to send the PO in with one price then go back and change the price to reflect the discount. It isn't horrible because I don't have to change each individual part number. That said it is still another step. I do suppose it just moves the process from the bookeeper making an adjustment to me so in reality it isn't anymore total labor for the company.

What is normal on this type of situation? Make the adjustments to the PO's so the cost of each part is as correct as possible or to make the adjsutments after the fact?

wouldn't your inventory cost come from the AP Invoices rather than the PO's? You match receipt to invoice, to PO, but I would assume you'd account for inventory cost most accurately from AP.