Billing. Can an external billing system push data to PrintJobManager (APJM)?

PRINTJOBMANAGER > FAQ's
Probably. APJM connects to external apps such as Quickbooks, Xero, etc. via Zapier.com (we include a Zapier account, you must have the QuickBooks, etc.). Depending on how you configure the Zapier connection, it can be bi-directional.