Is it possible to ADD the DVD navigation??

If the only car available in the color I want is one without navigation, is
it possible for the dealer to add the factory original in dash OEM DVD
navigation system?

Another option I'm curious about being dealer installable or end user
installable is xenon headlights. Is this just a matter of ordering up the
xenon lights off the net and putting them in myself? or is there different
wiring, any electronics anywhere, any difference in the dashboard icons,

Just out of curiousity, and this is probably a stupid idea that might hurt
the value of the car, but is it possible to change the color of the car very
easily? I mean, to get a factory quality paint finish would likely mean
disassembling the car down to the frame right? probably not a good idea?