I don't like the 'stability issues' inherent with tall, long-wheelbase vans. I've seen a couple of news stories on bad accidents caused by these becoming unstable in wet, windy conditions and going out of control.
I'd shop around, and try and find as new of a 'bus' as you can - a wider, dual-rear tire small bus, like what an ambulance would be built on....just looks much more stable to me.
JMO....