My first advice would be, look for an GOOD independent mechanic to work on your car, once you find it. Keep him!
A lot of people on this site, do their own basic maintenance (including me). Stay away from the MB dealers if you can, where you become a dollar sign (with a few exceptions, of course).
Use the search function on the upper right corner and you will find X0,000 listings under oil. Lots of reading...