is it possible to let the customer notes appear on the invoice? As we might sometimes forget to include it in the invoice
Adding the customer notes on the invoice is unsupported. However, you can add it in the message section of your invoice. Let me guide you through how.
I've attached a screenshot for you.
Please read this handy article for more information about notes: Add and use notes.
Feel free to check our site for future reference regarding: Income and expenses.
Let me know if you have other concerns. I'd be sure to reply anytime soon.