This is my second Mercedes. Originally I had no desire to own another MB. My first MB was a 2001 C240 with almost every option in it, but I got rid of it because of electronic problems and not knowing the common problem with the crankshaft position sensor ("CPS") failing from heat from the engine and transmission housing at the back of the engine in ALL MB C Class. Frankly, I'm surprised MB has failed to address and eliminate this very dangerous condition, especially at highway speeds. Anyway, the 1999 MB C280 is an enjoyable car. The CPS is a problem but just keep two new ones at hand and change every 30,000 miles or if the car unexpedly stalls in high temperature environments. Each CPS is about $48, but it's an easy fix with a universal socket (the Torx socket is hard to find), save yourself $400+ ahaving the shop do it. The engine is strong, efficient, yet simple and easy to understand mechanically. Failing valve cover gaskets tend to be the main problem in this line at high miles but straightforward to fix. Replacing plugs and coil packs are easy, just be patient doing the work. Getting in and out of the car can be tight for those who are above 6' tall like me. But the interior is comfortable and logical. Just wish I had AC vents to the back like my 2001 and a back shade cover in the back. Steering is solid and confident but be ready to replace the entire drag link assembly if you feel shuddering in the steering wheel at highway speeds or notice uneven wear on the inside and outside of the front tires. I got a Lemforder 2024600505 part to replace the whole linkage for about $155. Climate controls are clear but not easy to change temperatures quickly. Push buttons to raise or lower temp is laborious. Knowing what I know about the costs of fixing a MB I found that learning to fix it myself has been a blessing. I really understand the car well. The MB is engineered very well to a point of simplicity. The 1999 MB C280 is a great car that is easy to work on and learn from but not expensive to buy. Just remember to have an extra CPS at the ready.
I bought the brilliant silver C280 from a wealthy family in Westchester County, NY in March of 2018 with 24k miles - yes that's an average of 1,200 miles per year! As an owner of '91 300E & '97 E320 I am well versed in these cars. Little did I know that the V6 is a huge improvement over the I6. Many speak of the W124 & M103/4 as the holy grail of MB. Having replaced the water pump and now with the gasket leaks (oil in colant) on the M103 from the W124, I believe the V6 is much better. I see many owners with 200k+ miles on these M112 engines without much repairs. I can see why. The engine is smooth and powerful without much drama when pushed. MPG is not that great and headliner is starting to sag. But, the car looks great and feels like a proper MB, solid! I plan on driving and enjoying this beautiful car for many many miles.
I bought my 1999 C230 Kompressor from an owner who bought it new in 1999. For its age this car still looks and feels great. I should easily get past 250,000+ miles because it's been very well taken care of. Problems so far only seem to be a ghost in the electrical system. Sometimes electrical things work, sometimes, not. Replaced center link and rear differential seals have a small leak but I'm just keeping an eye on that for now.
I have owned a 1999 C230 for 18 flawless years of reliability (changed a few light bulbs and done routine maintenance, that's it in 115,000 miles). What amazes me the most is how new the car feels, with not a squeak or rattle (something I could not say for an Audi I purchased in the late 1980's which was falling apart after 10 years). The interior seems as new as the day I purchased it, with no deterioration of the dash or seats. It continues to feel like a single solid piece of steel on the road with more that adequate acceleration, handling, and comfort. The independent repair shop mechanic talks of how he "loves the 99 C class, these were great cars."
You should check the service records on CarMax for sure. If it's been well loved, this car will last you forever. It's comfortable and you can be really confident driving it for view ability, NO blind spots, great instrumentation including cruise and wipers. Ours has 104,000 miles since '99 which is unbelievable. We had it repainted the same as the orig color (silver), had a new headliner put in, and had a leaky valve fixed. Our ignition system did fail at 103,000 mi after we replaced our key! Be sure not to buy a new key without them testing the ignition switch first :) Lesson learned by all of us. I would recommend this car to all families, older drivers and all in between. BOSE sound system is amazing!! Love this thing!