You can write an authorisation letter to collect documents addressing the branch manager mentioning the details of the authorised person. These samples will help you in creating a perfect authorization letter.Check out the samples of authorization letters to collect documents. Check how to write an authorization letter to collect documents. Download an agent authorization letter template to give legal permission to another person to act on your behalf. Specify the Purpose: Clearly state why you're writing this. Empower a trusted representative with an Authorization Letter. Make a free Authorization Letter in minutes with our customizable template. CocoDoc collected lots of free authorisation letter to collect documents for our users. Instructions for completing the Third Party Letter of Authorization (LOA).