power steering fluid leaks? where is the reservoir for this located?

Looking at the engine, the small black reservoir at the top/front/right side of the engine, is the power steering fluid reservoir. There are two common leaks associated with that area. 1) The power steering return line leaking at the fitting. 2) The o-ring that seals the reservoir to the pump. Both should be fairly inexpensive to repair at any M-B dealership. In addition, I recommend having the repair done at a dealership to insure that the proper synthetic hydraulic fluid is used to fill the system. Finally, there is another common issue with the p.s. reservoir. If the fluid appears to be coming out of the top, the baffles in the reservoir may have gone bad causing excessive swirling of the fluid. That problem will let air into the fluid causing a noise and expanding the fluid causing it to leak out of the top.