its really better to use touchscreen... you can pick one up for about 300-400 dollars. you could probably get a carputer going for a starting price of about 750 including teh screen, and build it up from there. you can turn it into a gps/ point to point direction/map, game consol, mp3 storage, radio, rearview mirror, fuel management, etc.. you just have to buy the hardware to get the extras working.