I remember going to AMG in Affalterbach - they also build the Panzer'd models there. For the really top end stuff for heads of states and all... say a G-wagon or S-class... you can not even buy their cars! They are all leased! And when the car needs servicing... they trade you out into a new-er car. They don't want anyone taking their cars apart to see where any weaknesses are or how the car are put together! very interesting.
BTW... Audi, BMW and MB all make Panzer'd cars.