Set up a WO step called outside processing. Set up a misc PO code for the outside processing step. Issue a PO for the amount of the outside processing cost and reference the WO job # and step. When the item is returned with the added processing, receive against the PO (ROG) and the value is added to the WO job. To report on what is at the outside processor, use the open PO report as a reference. Not extremely pretty, but workable. You do have to make sure the PO has been received/paid before closing the WO though. Maybe @DebThomas has a better process.