Based on your description it sounds OK.
As it is a one owner car there must be a maintenance history, either in
the owner's shoe box or at the shop(s) where it was serviced. In light
of the busted odometer I'd insist on seeing the records that will
document the car's claimed mileage.
A compression test will verify the engine's condition and a drive the
transmission. The engine and transmission typically have similar lives -
250K to 300K miles - with regular maintenance.
If you will do the maintenance yourself buy the M-B paper manuals or the
C-D ROM; it's $ well spent.
This five is very reliable if it's well maintained. Oil & filter change
at 5K miles, valve adjustment at 15K miles and fuel, air, transmission,
power steering filters and transmission fluid change at 30K miles. You
do that and it will run for a long time.
These cars have relatively simple electrical systems, not a major item.