OK, now I see the use more clearly defined (the church thing). I really think, like ddndoug, you're going to be better served and have a more efficient experience with a truck and separate trailer. The riders will work out their rest stops as needed.
The cost of running and maintaining a Class C or Class A, your other options, are going to be greater than a truck and trailer. The cost of a full tire replacement on a Class A could be your entry price for a whole travel trailer, for example.
Since you're going to be interfacing with church folks, I'd assume that when you arrive there will be some of your needs met (food, socializing, etc) so the RV is mainly for sleeping, an occasional meal, and your daily constitution. If you plan to visit some attractions along the way, the truck can be used to easily access them.