Jennifer, et al.
We generate bills for fines for some of our members. These are usually
sent by email using what I believe are the stock triggers for this. The
emails are sent when the patron exceeds the fine count.
We may generate PDF bills for this for some of our members, but I'd need
to check that code to make certain, and I'm a bit busy with other things
at the moment.
It sounds like you're asking for something that Evergreen may not do out
of the box, but I think Bibliomation may have set up once for their
academic members. IIRC, they had something that would generate billing
notices for students near the end of the semester.
If you want more information about the usual fine notices, I can
probably look it up later.