suginami no getting around it you were rude
bdemir you need to get a new mechanic to take a look at this car, if you still want it. Do not keep giving money to this guy. Where are you located? Take your car to someone who has a clue. The vibration problem could be a lot of things like tire balancing if the steering is shaking. It could be anything!
Oh and at 164k miles surely you weren't expecting a car in above average condition. These benz cars are a sure fire way to go bankrupt if they have not been taking care of by their previous owners. A lot of owners ignore repair suggestions and when they can't ignore things any longer they patch it up the best they can and sell the car privately.
If you take it to a new mechanic that specializes in benz do not be suprised to get a long list of problems...sorry.