Robbie, if you want to know the "official" value of an M35, check out
http://www.redbookasiapacific.com/au/vehic...s.php?id=111363
I have a 2001 250t RS four and I can honestly tell you that it is as close to a flawless a car as you will find (for the money, of course).
It has enough power, great economy (I am at 9.1km/L at the moment - usually 680km each time I put in 70-73L), nice handling, HEAPS of great extras, Lots of room... Just an incredible machine....
Just make sure you get it in leather. Really tops it off.
Best of luck Mate.