Home Office Deduction

Hi, I work mostly from home, what information needs to be on the letter from my employer?

Your employer needs to write a letter stating that you are allowed to work from home, and that this included in your employment contract (if applicable). They could also include details about the following-

- approximate hours at home
- % commission of total income
- if there's no designated office space at your work, it would be worth mentioning this too

Check the questions at Can I deduct home office expenses? to ensure you qualify for the deduction.