Monaco, I am going to buy a black 1980 300sd in Las Vegas this coming Monday. It looks like you are having many problems on a 1980 300sd. Can you give me some advice on what to look for? The owner said it only has 45k on the motor. A/c, heater, and sun roof not working? How much do you think is going to cost me? He is asking $3600-4500. I am going to make a $3000 offer if the car is in good condition. What do you think?