I agree with Deanyel's post. Even with your mechanic, you will need to learn everything you can and do what you can , work with him, etc.

At the same time, the car's description sounds good.

Check to make sure basic major maintenance items have been done like the timing chain, very important.

These cars are excellent drivers for 3 to 4000 miles per year. I rode my car for nearly 10 years like that (bought it at 100,000) before I really had to roll-up my sleeves with it. the fact that you are putting low mileage on the car makes owning an old Mercedes a much better propostion in my subjective opinion.