Purchase order number

Business customers pay from a purchase order. The fleet's manager raises one for the job, the number comes to the shop, and when the invoice arrives the accounts office matches the two. An invoice with no PO number goes to a pile; owners in an AutoShopOwner thread on fleet billing describe payment from some fleet customers taking two to three months even when everything matches, and an unmatched invoice is slower than that.

A PO number is issued before the work and quoted on the invoice after it, so the shop has to hold it on the order from the first call, not add it at the counter. The useful design is a rule on the account rather than a field on the order: whether this customer requires a PO, so the invoice cannot close without one when the rule is on, and the advisor is asked for it when the order is opened.

The PO number sits beside the vehicle number on the invoice and on the month's statement, which is the pair the fleet's clerk reads first. The fleet account terms post has the rest of the list to settle before the first PO.

In Wrenchy the PO requirement is a rule on the business account, and the number is held on the order.