Cazca

The car is very nice, but I have a few quesitons. 1.The car doesn't have Nav, is there a way to unlock it or add it on to the current in dash screen? 2. I need rear dvd screens/playing capabilities. What are my options? I'm open to headrest or flipdown. Would love to be able to put the dvd into the dash and play on the rear screens. any help is appreciated.