The Sales Invoices have a number of routine emails that can be be sent i.e." ‘Standard’ ‘Reminder 1’ ‘Reminder 2’ ‘Reminder 3’ " for the purpose of credit control.
The Estimates sent to clients could also have a similar facilty i.e " ‘Standard’ ‘Purchase Order Acknowledged’ ‘Advice of date agreed for the job’ ".
The examples that I provide as additional routine emails for estimates are based on a contractor working with a client where the client sends an order for completion at a date to be fixed when resources allow.
Perhaps my request has more complications than I have considered, but acknowledging a message raised via “Quick File System Bot - Estimate #00323 Accepted” would definately be a good way of confirming receipt of an order received from a customer.