What I learned while I was getting my 240D back up to snuff:

Oil Change
Valve Adjustment
Belt Replacement
Glow Plug Replacement
Idle Speed Adjustment Knob
Driveshaft Carrier Bearing
Flex Discs
Transmission/Diff Fluid Change
Shifter Bushings
Door Strikers
Hubcap Brackets

Valve Adjustment Wrenches:
https://mercedessource.com/store/615...

Glow Plug Upgrade:
https://mercedessource.com/node/726

Driveshaft Carrier Bearing Kit:
https://mercedessource.com/store/123...

All other parts from AutoHausAZ or RockAuto.