We often receive Inventory but edit the Purchase Invoice to add the cost after as we do not have the cost on the packing slip and have yet to receive the invoice. It would be helpful if the system either allowed us to edit an Invoice with Zero Dollars to add the cost after the fact or if the system would at least give us a warning that we are about to post an Invoice for Zero Dollars. This way we say no to posting the zero dollar invoice and instead change it to 0.01 until we get the invoice and can edit the cost of goods.