I have noticed a difference since we switched to FIFO cost basis for all products/assemblies a few months ago, between the sum cost of the components of a BOM (Manufacturing > Bills of Materials > [assembly] > Print BOM Cost) and the Unit Cost of the assembly Product (Inventory > Products > [assembly product] > Cost).  This shouldn't be the case, since the quantity of the assembly product is 0, because I am making this particular assembly shortly before delivering it.

I was able to determine the total value difference using the Product Moves and exporting the "Stock Move/Value" field for both components and assembly for a single manufacturing order.  The value of the components removed from inventory was $362.19, while the value of the assembly added to inventory was $450.69 , a difference of $88.50 .  All components are Stockable product type.  The COGS of the assembly from the Product Move of the delivery was  $450.69 .  While this matched the incoming value of the assembly, the value change increase during manufacturing means I effectively overreported my COGS to the accountant: not good!

Does anyone have any ideas what the source of this error might be, or a way to resolve it so the value for outgoing components and incoming assembly matches?

~John
Odoo 11.0-20180613 (Community Edition)