Great thanks, to be clear, because I do not want any mistakes in my taxes, I recently moved in with my girlfriend, but her apt does not have the space for me to set up an office i need to run my business. So I have been going back to my old apartment, that I am now using my old bedroom for an office to work 5 days a week, from 9-5. Can I essentially continue renting my room in my old apartment, that I share with a roommate who lives in the other side of the apt, for the purposes of office space, and deduct the expenses as you said, under building and land rental?