Same thing actually happened to me when i moved out of college senior year be and my roommate were being charged 600 for damages to our room, but actually before we left we had completely redone to the room to how the college wanted it including painting a certain color and cleaning. They tried to come back and say it needed all kinds of repairs, cleaning and more. So i finally appealed it. I asked for all kinds of crazy specifics like, was it documented how many people worked on the jobs, precisely how much time was used, what kind of material was used. Just as much inanspecifics as possible. I submitted all the requested info the person in charge of housing. Then i haunted him one every two days for the information finally after a month he said that everything was fine and we would not have to pay. So i say ask much specifics as possible and just be on top of every detail. Also harp on issues you find. People just tend to give up if you keep going after something.