What happens if the box is unchecked for 'value rebuildables at zero cost'?

Rebuildable items were set up to be valued at zero cost and all reside in a non-asset subinventory. Wewould now like to change this now in order to carry a value for rebuildables. What will happen when the checkbox for 'value rebuildables at zero cost is unchecked? Will the items still be able to be issued out of inventory? Will they need to be moved to an asset subinventory? What happens with the accounting? Will a cost need to be added?