7.4. Sales – Customer Invoices 7.4.1. How to issue a Customer Invoice 7.4.2. How to invoice a shipping cost to the customer 7.4.3. How to register payment for Customer Invoice 7.4.4. How to manually match payment & invoice 7.4.5. How to setup discount for early payment 7.4.6. How to modify a validated invoice 7.4.7. How to edit or refund an invoice 7.4.8. Where to check Receivable Ledger 7.4.9. How to automate Customer follow-up