Adding part of the rent for professional activities to expenses

Hi,

What is the best way to add the monthly rent expense?

I paid one monthly rent to the owner (split rent is not possible). I also know what percentage of the rent I can claim. But I’m wondering what information needs to be stated in the file I submit. Just a pDF with a description of the rooms used and the percentage of the total?

Bonus question: can I do this automatic monthly?

Many thanks for your help!