IMPORTANT  !!
With the New 9  Speed Fiat Ducato 7.4 metre motorhome with a Garage  , You can NOT have  the vehicle on a light chassis  as there will be NO payload
The Fiat 9 speed transmission and also engine is so much heavier than the 6 speed Automatic
A Light Chassis means  manufacturers  specifications is 3500kg  Maximum -  then it can be extended to 3650kg to save diesel carbon tax 

IT  STILL WILL NOT  GIVE YOU  MUCH OF A PAYLOAD TO CARRY IN THE MOTORHOME

TAKE IT TO WEIGH IT  AT THE   REFUSE  STATION !!!