Last buy price vs FIFO cost price

On the system, each product has two cost prices:

1. Last buy price: this is the last purchased price, this can be changed at any time (from the products edit page or via import). It is only used for future new purchase orders, and for suggesting the purchase order price (given that there is no supplier price defined).
2. Product's FIFO or total weighted average cost: this is system calculated and driven for any items that have been receipted and costed previously. When the last buy price is changed, it will not affect this cost. After a purchase order (or inventory adjustment) is receipted and costed, this cost price is then re-evaluated and updated. All sales reports including the price tier export data uses this cost. It is the actual stock receipted or landed cost.