You can use the Invoice feature to write and convey messages directly to your customers in QuickBooks Self-Employed, abbe. I can guide you through the process.
Before we move forward, could please share what type of letter you are trying to write? Any details you provide will help us determine the best approach.
If you want to use the Invoices feature in QuickBooks Self-Employed. Here is the step-by-step:
Navigate to the Invoices tab.
Fill out the form, you can utilize the Message section to compose a letter to your customer.