A Project Manager can mark work as Done on Open Purchase Orders (or Work Orders) through a selected stage (phase), AND can deduct an amount from the PO, The Project Manager can ALSO write notes related to the PO that the back office and big boss can see when posting bills from trades or suppliers in CHS.
The accounting staff can search Open Purchase Orders for ones that have been marked that work is done and quickly create a payables bill to pay directly from the PO,