I am looking into purchasing a 2001 X5 for my daily driver. I have found a nice one locally but has one potentially serious problem. The factory navigation system does not work. Also, the stereo only works for literally 1-2 minutes and then shuts off. Is this a common problem in early X5s? Is this an easy fix? If not, would it be easy the replace the factory nav/headunit with an after market piece "non-nav?" The owner said the dealer quoted him four thousand dollars to replace the computers? I don't really care about having the NAV but I need the stereo to work.

Thanks!

PS: Here is a picture of the interior that the owner sent me. He said it had the upgraded sound system. Can you tell if it does from this pic?