<prompt> Human: Hi everyone. First time poster in personal finance. I have a little bit of a sticky situation that doesnt affect me or my wife. It affects my wifes 21 year old cousin in the marines. The cousin has only been in the military for 1 year and is still getting paid potatoes since hes only an E-3. This is his first real job and source of income. So hes not used to all this money. Right now, his dad and step-mom have asked him to co-sign for a loan refinance on a house that he wont be living in any time soon. Not only that, they want him to contribute a some of his income to the monthly payment. He doesnt know anything about personal finance and credit. So hes been going through with this, signing documents and providing pay stubs. Although the refinance isnt complete, hes been contributing 500month already to them. This leaves him broke and unable to really do anything funexciting like a young marine should be doing in Japan. Not to mention hes not putting anything away in a retirement account or savings account. The dad works as a truck driver and the step-mom doesnt work but gets disability from the state. They have been promising him that he will see a LOT of money in the far future. But they also say they will never sell the house and instead keep it in the family. This doesnt make much sense to me. I understand if they default on the mortgage payment, hell be held accountable as well and it will screw his credit. Is there anything anyone can see that would positively impact him? Or any other negative aspects of this shady deal?Thanks in advance. EDIT: thanks everyone for your feedback. Im forwarding everything to my wife who is relaying to her cousin. I really appreciate your thoughtsopinions on this. I knew it was a bad idea the second it was brought to my attention. Just wanted to be sure my thoughts are aligned with the general consensus.  <response>: Bad idea. He could permanently damage his credit AND permanently damage the family relationship. The family relationship may become damaged anyway regardless. But why ALSO fuck up his credit? 