YTA. Why not ask her to clean the dishes? Or some other typical teen chores in return for her having your office? I doubt her relatives gave her birthday money to give to you instead… It’s simple, you consider her your daughter therefore she is your responsibility until she is an adult. She can’t work, or earn a wage so why make her pay ‘rent’ when she doesn’t have a job and can’t even get a job yet! She’s 12, if you really want the money why not pay her for jobs around the house instead, and then at the end of the month she can pay you her $5 rent and anything extra she earns she can keep. That’s more of a valuable lesson than making her give up her birthday money.