NAVI sytem in 2005 C230k
 

Thinking of buying a used Navi system. The buyer says its a DVD player too..does that make sense? Is the single DVD/CD imput for both? Also, what is a good price for a used on in excellent condition. The unit came from an 2005 C230 and would be going in a 2005 C230. Should I be pretty sure that it would fit? Also, the DVD is for Europe. Is there anyone out there that would let me rent there DVD's for programming or would I have to go lay it all out at the dealership? Since I purchased this car used with 9000 miles I don't know the value of the Navi system. How much was adding this option on when the car was new? Will it ad $ value to my car? Any idea of how much?
Thanks for all your help!
rob