Add file upload field to appointments+ admin side

On the admin side of appointments+ you can see the detail of each appointment and assign notes about that customer. Is there a way to add a file upload field to this area so I can upload customer waivers while in this menu?

I used CIMY User Fields to add the fields I want in the customer’s user profile (admin visible only) but these only show in the user profile. I’d rather be able to upload the waiver from the appointment’s summary rather than have to navigate to the profile of each user.

any thoughts or ideas?