ProfitBooks offers facility to add certain information which will be printed permanently on each invoice.
This feature can be used for printing:
1) Bank Account Details for receiving money
2) Payment Terms and Conditions
3) Late Payment Fees
4) Delivery Details
5) Warranty Terms
6) Return or Replacement Policy
Or any other details which you feel will make your terms of sale more clear.
You can read this detailed article to Writing Invoice Payment Terms
Please follow these steps to include the Customer Notes and Terms and Conditions on Invoice.
Please go to Settings > Invoice Settings
Once you update the details on the page, it will start appearing on each Invoice.