<prompt> Human: Dad owes 80,000 on a commercial property that was recently appraised at 800,000. In the past month, he had two tenants move out, and wants to refinance with the bank in order to lower his monthly payment, but his credit isnt the greatest. He asked me to co-sign so he could get a better rate. I know that if he doesnt pay the mortgage, my credit could take a big hit, and I could be on the line for the full amount. Should I go through with this? What steps should I take to protect myself? I am 25, making 85k a year with only a few grand debt in student loans, and renting a small place in a different city.  <response>: When you co-sign, its saying that you agree to pay whatever is due, which could be the accumulation of unpaid monthly balances, interest charges and penalties, or even the entire balance.You want to help your dad, but this is not a good financial decision, and these sorts of arrangements often become a source of stress. If your dad has bad credit, its for a reason -- like missing payments. The bank doesnt trust him alone to pay back the mortgage, which is why it wasnt a cosigner. If the bank doesnt trust him, should you? 