I have a 2002 C240, very few miles.

Before I mention my problems, the fact you mentioned made in Germany as opposed to a Brazil made vehicle I think is GOOD. Also with the mileage you have many potential issues could/should already have made theselves apparent.

Many people have had an ESP - electronic stabilty capabilty on slippery or high power driving situations - this is repaired by some work on the wiring harness. This repiair once done should present no more new problems.

I have had a few light/security/autolocking sensor problems most fixed under warranty, the one that wasn't cost around $400 for a new module installed.

Very IMPORTANT, these cars requires a GOOD battery, I change out my battery every four years on this car. If the battery is NOT fully charged all kind of weird malfunction warnings occur. I think one of the reasons I was having electrical issues was due to a worn battery that the first dealer didn't catch - one reason the car had so few miles.

Also a great site for investigating Mercedes repair and maintenance is
www.mbWholesaleParts.com search for the STARTUNED link and use the search for you car model. Startuned is an official Mercedes site for mechanics

Another pure 203 model site is www.mbklasse.com if you play around at this site you'll see issues owners have had, and lots of the forum members drive their cars extremely hard.

Overall my C240 is an unbelievable car, it is one of the quietest cars I have ever been in. A wagon version normally creates a bit more boom sound form the cavernous space in the rear.
Be sure you research what tires work well on the vehicle when it is time to replace them.

Finally, what I like about the earlier 203's is the fantastic dash display, the big orange readout of the display is so easy.

Overall the C240 was a very good purchase for me, I don't regret it at all.