<prompt> Human: I am buying a house. My girlfriend will live in it, but will not be on the mortgage. I have an idea of what seems fair, in terms of her contribution, but thought Id muster opinion on it.Ive had to put down a very large deposit, which has near wiped me out. As a result the mortgage is cheap. We currently share 775 bills in rent. The mortgage will be about 450.My thought was for her to pay half the mortgage 5 i.e 52.5. She will also be responsible for half of any typical and recurring payments i.e. - mortgage setup fees it was cheaper overall to pay 775 upfront in mortgage fees, home contents insurance, utilities. She will also be responsible for half of home improvements we will be doing and agree we want to do, this might be a bit of decorating, but also things like adding loft insulation which will save us both on bills in the long term, and if we had to replace a window or such. If anything big were to happen, that would be a separate issue. So perhaps half of all home improvements below 1000?Any specific costs associated with the purchase solicitors fees etc. I am covering 100 myself.Of course, we will ensure there is documentation of everything and any agreements.Sound reasonable?Extra info: whilst not rich, were both financially comfortable. We also never argue about money or anything and are very reasonable relaxed people. In fact I help sort most of her financial stuff, which is why I want opinion as now I am an invested party in her finances, whereas before I just helped her with savings and investment.  <response>: Just charge her what you think would be fair to any tenant, based on the market in your area. No, it does not sound at all reasonable to charge her for maintenance costs or other homeowner responsibilities - she is not a homeowner, shes your tenant. You say you wiped yourself out financially putting a downpayment on the house - if you did that counting on money from her, that was the moment to ask her for her financial support, and give her some say in the decision. That would have been reasonable and fair minded.To be frank - assuming that shes staying with you because she is your lover, not because its a just a way to be housed - it is inherently problematic that you are figuring out the details of what youll charge her AFTER you already have a committment from her to move in with you. Thats no way at all to have friend, nevermind a lover and romantic partner. just ask her for market rate... whether thats more or less than what you are proposing here. ...and if your relationship with her is the priority, ask her as though she has some say... because theres a benefit to you of having her choose you, apart from the money. 