When you forward an email to the unique intake email address affiliated with your Hubdoc account, you can add a note to the body of the email, and this note will appear in the "Notes" section within the Hubdoc web application. If you have attachments on the email, then the notes will appear for all attached documents.
To format the note, please type the message into your email like this:
#note your message #note
Please refer to these screens shots for a guide:
Hubdoc Web Application