Process one-time invoices

Trigger: A vendor submits an invoice for a non-recurring good or service lacking a standard purchase order.

1. Receive one-time invoice document
2. Verify vendor credentials and compliance details
3. Determine and assign general ledger codes manually
4. Route to department head for ad-hoc approval
5. Post approved invoice to the accounts payable subledger

Outcome: The one-time invoice is approved, accurately coded, and staged for payment in the accounts payable system.