What to look for when buying 1998 C230?

"cp"

Missing 'Kompressor', inadequate torque, low performance.

Look at the 1999s the C230 gets a supercharger and hence has a lot more power.

Overall it is a sweet car. As with most Mercedes, a lot of little things can be/go wrong.

Newer mercedes use a maintenance schedule called FSS (Flexible service). The car has sensors that tell you when stuff has to be done, like oil change, etc. Now, these cars go 10,000-12,000 miles between oil changes (they use synthetic oil). So, you want to double check the maintenance records, and make sure stuff was done. A lot of owners do oil changes in between the FFS times, which is a good thing.