<prompt> Human: Please no sarcastic dont remarks - were it anyone else i wouldnt and we can afford payments in a worst case scenarioDoes this make us part owners of the house? Are there tax issues i need to worry about? What are some general rules to know? I know how cosigning works in most cases but I know houses can be differentEdit: I forgot to add for those wondering - the only reason they need a cosign is because she hasnt been at her job long enough kid and a bad marriage left her out of work for a while her credit and current income is well above whats needed for the loan  <response>: we can afford payments in a worst case scenario; Does this make us part owners of the house?Not to sound rude, but these two quotes make me fear that youre not experienced enough to understand the gravity of the mistake youre about to make. How do you know youll always be ready to pay her payments? If you have the money, just buy her the house, but I dont think thats what you mean. And of course your question of whether you become a part owner... thats so very fundamental. Its a powderkeg. If you go through with it, certainly get a prenup - cause youll almost surely be divorcing if you marry. Also get a detailed document signed by all three of you of precisely how youll handle the asset when things fall apart, i.e. marriage breakup, general resentment, or if something like this kid and a bad marriage left her out of work for a while happens to you.Sorry to be harsh, but a little pain now is better than signing up for endless widespread agony and litigation later. In the simplist terms, its a disaster waiting to happen. 