We recently added a bit more flexibility around updating the purchase price after receiving. You are now able to change the purchase price (select ‘Yes’ for ‘Different billed subtotal?’ and enter the new subtotal in the ‘Billed Subtotal’ field), if the items received have not been consumed (no inventory picks against those items). This is a small change from the previous functionality where any inventory transactions against the item prevented changing the purchase price. We're continuing to work on expanding this functionality out even more.