What should my dad do?

My dad hired this man to fix up a house he rents. This person proved to be inresponsible and an alcoholic! My dad and him did a contract forthe amount he was going to charge. My dad has receipts sign by both of every payment the man got. He didnt do some of the stuff he said in the contract so my dad deducted that from the amout due. My dad has payed him everything he owes! The man calls my dad all day even at his work asking for his money. Mydad has told him to come to the house to talk and prove him he doesn owe him. He never comes and wants to send his daughter. What should my daddo?? This person is a drug addict alcoholic and who knows my dad was dumb to trust him