Congrats on the window regulator being fixed. But I think I got you beat on the cheapest MB fix.
Took ML320 to dealer last week for annual state inspection, had soundpanels reglued, and AAM foglight codes enabled.
Total cost...$25.50!!!
Okay, the soundpanels were done under warranty so that's cheating, but I have NEVER gotten out of the dealership that cheaply!!! Usually, my wallet hurts!