you need to check out a site dedicated to Coaches where they can address your questions with collective experience and authority. They KNOW Coaches. A well known site is:
https://www.busconversionmagazine.com
Vanhools as a rule are more complicated and European in their design, engineering, construction, and parts usage. I've driven them for years for several companies and my experience is they seem to break things all the time and constantly giving me fits when stuff doesn't work as it should. Lots of plastic used everywhere and again overly complicated systems. You'll be well advised to find and nurture a knowledgeable mechanic/shop who knows them and how to work on and get parts for them. As all coaches are, Vanhools are an order of magnitude more complex and expensive to work on, and keep on the road than a simpler school bus will ever be. Keep that in mind and be prepared for a truly Epic learning experience.
One other thing. Vanhools don't have a lot of ground clearance to go off pavement. They do have a nifty system to adjust the ride height from the driver seat....which may help a little, when it works, which is another story. You'll also notice, real fast, that the rocker switch labeling is worn off many switches and it's all merely symbols which means you need to decipher what they all do. If worn off it's even worse. Find and use a user/repair manual to show you the switches, their locations, and what it is they all do. There's a lot of switches on all Vanhools.
All dimensions and ground clearance parameters are pretty much optimized for paved operations. I had many thrills and more than once made passengers walk into various camps I was supposed to drive the bus into. All coaches are made primarily for on pavement use and a few manage to go into the rough and tumble better than others, but Vanhools aren't one of them. Take it easy until you learn the limits of your coach.
Driving Vanhools with other operators confirmed my choice of MCI's as the only one for me. Way too many reasons to go into. But it boils down to great design, simple as coaches go, systems, built and made to be reliable and easy to get parts and repair. This is what most Charter Operators look for, and doubly important for a private individual with limited financial resources. When the time comes, that's what I'll be getting for sure, a solid MCI, that I also have decades of experience driving so I'll know what to look for.