The first in First Out (FIFO) method retains the price of the product on the basis of the FIFO of the product and the Average Cost takes the average of the prices. We can first check what happens if we set a standard price. Then we can go to Inventory Valuation.
Now go to invoice->configuration->chart of account->under current account add *stock valuation account * stock interim account(Delivered).
Under current liabilities add * stock intering account (Received).
Now Go to inventory configuration ->product categories->create fifo as one category.
Then create a new product, give category as fifo. Create two or more purchase quotation.
Create one Sales quotation:
Now go to new created product and check the cost,