after working on these jeep Cherokee's for 3 years during my career with Chrysler I can honestly say that these vehicles come riddled with issues, its only a matter of time before these issues pop up one after another after another after another after another.
Flex pipe's (Breaks)
Oil cooler (Leaks oil)
Injectors (stop working, usually cylinder 3)
Vent temperature sensors (Malfunction)
Wheel Bearings (Wear out)
Brake rotors (normal rusty rot)
Lower front ball joints (Premature wear on early production models)
Radio Faults (Software issues)
Lights and Messages on the dash like you've never seen before
Rear shock absorbers (blow out)
RDM (Rear drive modules fail and set fault codes)
Buttons in the steering wheel go dead

I'm sure i'm missing 50 more things that go bad on these but you get the point.