Pictures would help a lot, engine left and right, driver seat and dash, exterior front, rear and sides.
Offer $500.00 if it will not run.
$1500.00 is not bad if it runs and has minor issues.
A rear main or front transmission seal is not in my opinion minor.
Pulling the powertrain is not a minor operation, and is a mess with oil leaks.
Check the air cleaner oil breather drain tube, if it is not seated and sealed top and bottom, huge amounts of oil blow down by the starter and can fool none MB people to think a seal is gone.
The sunroof is a PIA but can be fixed or replaced.
The injector sounds like a rubber fuel return hose cracked, no big deal.

__________________
ASE Master Mechanic

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D

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