Class 8 would be the best way to go.
Depending on length, and options ie., sleeper etc., with the built on ramp. I would consider getting a hitch-buddy for towing your trailer. For more info visit
http://www.hitch-buddy.com
Alot of folks who have purchased various model Motorcoaches are using that set-up and it seems to work very well for their needs.
Hope that helps...
Ciao,
Ace