Rick,
I got one at Pep Boys for $89.00 plus tax. The book that comes with it is pretty much useless, but I have the MB publication that gives descriptions of all the codes and locations of related components. I have repaired my 129 3 times with these tools very easily. It is amazing how the light comes on, I plug in the reader, take the code to the book, buy the part, and install it. That is Easy! If you need help with codes after you get your scanner let me know. Good luck!
Brian

__________________
Brian W. Heitman

www.MBCA.org/northtexas

Join MBCA!!!