This should give you a good guide: I just picked my car up today after having the head gasket replaced on my 93 300E2.8. It was done by Premier Motors, the Albuquerque Mercedes dealer, for $896. The price included a new radiator cap and an oil change. Since the car only had 64,000 miles, it did not need a valve job but last week I saw gobs of oil in the water and I knew it had to be done. It was leaking a little on the floor but I could never detect any change in level between oil changes every 3000 miles. I saw the old gasket and there were two or three areas where the material was just falling apart although I could not really tell where the actual oil to water leak was at.