In general the payment of invoices is tied to the receiving workflows. 

System running single line POs generally still has multi line invoices.

Mostly the one off vendors that are not setup for EDI but there may still be a significant amount of ordering through them.

Kimberly P, manual often come through email and are electronic database orders. Often start order using notes and payment history.

Problematic about the find POL

• Not knowing what has been selected to be added.
• It is not clear in what order invoice lines will be added. Ideally we could influence the order of the lines because the invoice from the vendor has everything in a specific order.

Creating orders from amazon the invoice will not include any order detail so we need to find the FOLIO order by title

Many clicks for the single line invoice. Create from PO would be helpful here in saving the user clicks.

A number of vendors do not send credit invoices through EDI as they are often 1 or 2 lines. So they are entered by hand.

When ordering a membership we generally pay for the membership on a single POL but the order may have other POLs representing the additional things included with the membership.

If creating multi-line firm orders you may have certain titles arrive at different times on different invoices. Meaning not all POLs will appear on the same invoice.

The workflow required to create invoice from receiving pieces? (Is this possible? Is it really important to users?) 

See deferred requirements above. There are libraries that have invoicing workflow that are very closely tied to receiving. This can span one-time and ongoing orders.