Great choice on the X5. I was going to suggest that you avoid retrofitting the navigation. Although it can be done, it would be extremely cumbersome and expensive. If you want an in-dash navigation, I would suggest looking at the Pioneer AVIC D1 which many on the forum have installed in the X5. This unit has navigation, DVD, bluetooth, etc. Eclipse also makes a nice double din navigation, with all the goodies. As to your other questions, I will let someone more experienced jump in.:welcome: