So a good friend of mine just bought a '98 528i (somewhat on a whim). He is not mechanically inclined. I went with him to look at the car, but since I have very little BMW knowledge and no chance to research, I couldn't do much other than run the standard "make sure everything works right" pre-buying checklist. Now I need to know what to tell him to do next.
The car is a non-sport package with 75k miles. It's a stick. It drives very nicely and has apparently been well-taken care of (immaculate underhood, fluids fresh and up to level, four matching Yokohamas, clean carfax) but did not come with any maintenance records.
I'm aware that BMW treated cooling systems as wear items in this era, but what specifically should he think about replacing?
Also, the car has the audiophile package with the huge, non-standard shaped stereo deck. Is there an aftermarket kit that will allow a regular DIN receiver to plug in and still use the factory amps and CD changer?

