The X5 is prewired for the CD changer on the left side of the cargo area. I don't think the changer would fit in the console or the glovebox without modification and rewiring. All X5's are built to order, whether by the dealer or individual. If the dealer ordered this X5 the changer was probably left off intentionally as to make more money installing it later. If I read your post correctly, it sounds as if the dealer is trying to convince you that the navigation system will not work without a changer installed. This is not true. The only reason to need a changer is if you want to listen to CDs and the head unit has the cassette.