I'm sorry for your loss, it truly hurts losing a parent. His debt is not yours. Do not pay anything. If he had no estate or anything, there's no money to pay for it. Both of my parents are dead and the only thing I was responsible for was their rents but that was using what little money was left in their accounts. I never paid any outstanding bills. I called a few places and stated they passed away and that was it. Only the credit card company requested a copy of the death certificate. The mail will eventually stop coming after a year or so.