Check out this thread, and read the buyer guides posted as pdfs (not the acrobat links in first post)
List out all the known maintenance issues. As previously stated, if you do the straightforward stuff yourself you'll save a lot of money.
I LIKE OLDER BMWS, PLEASE HELP ME
Fern Green 99 M3
, Conforti Shark Software, Conforti CAI, Dinan Exhaust. Stamped LTWs, 235x40 square, OEM Hella heads, ///M
Pedal Kit, Clear Corners, OEM Rear Spoiler, CD43 stereo. MRegistry listing here
Le Mans 2002 M5
, Black/Titanium, Rogue SSK, Dinan exhaust, PSS9 coilovers, Euro rotors, iPod integration. MRegistry listing here