Mold in the refrigerator, how can i make sure its ok?

Im moving into a new apt and the refrigerator they have in there now has black mold in the freezer and smells terrible. Obviously they have to clean and fix that before i move in, if not replace it. How do i clean it to make sure its disinfected and safe to use, im having a baby soon and i want to know that its ok to use and we wont get sick or anything. any suggestions??