As an owner of a 93 300E 3.2, all I can say is that once I got to the 100K mark, the heat and wear has taken its toll on a number of items.
I have replaced the radiator, water pump, and resovoir tank not long ago, and had the defective wiring harness replaced last year. OVP, temperature sensor, and belt tensioner has also been replaced.
The air conditioner evaporator also died last year, so make sure you have the A/C checked out thouroughly.
I just lost another window mechanism last night (rear passenger), and it failed the same way that the same unit on the other door did last year.
Some dash bulbs have burned out, but I haven't replaced the burned out illumination bulbs in the radio.
Most of the items I've mentioned have not been expensive (under $300) except for the evaporator, but that was fixed under an extended warranty. I have done a lot of these repairs myself (thanks to the forum).
Fortunately, I haven't had any drivetrain problems yet. I think proper maintenance keeps that in check.
This is my daily driver, so I expect that as the car gets older it will require a lot of attention.
My guess is that the previous owner got tired of chasing down all of the annoying little problems and decided to cut his losses (that's how I got rid of the Jag). So definitely have the car check out by a trusted mechanic, because many of the above parts have not been replaced...
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car