I am puzzled as to the thread topic of super green.
If that is your way of saying you are committed to repurposing old stuff and giving it a second lift, you sure came to the right place.
If that is your way of saying you are committed to saving the environment by driving a bus that is running on waste vegetable oil or bio-diesel you may be a bit disappointed here. Not by the welcome but by the way in which many have tried that and most have not been at all successful.
My most important tip is for you to decide which bus is the right bus for you. There is no one perfect bus for everyone but there is one bus that might be perfect for you. But you have to decide which parameters will work the best for you. If you really want a rear engine bus with big HP and highway gears you really do not want to waste your time looking at shorty conventionals.
And lastly, do not purchase anything with rust. You can do a lot to convert rust but like cancer, rust does not just go away. It is very easy to spend countless hours and lots of $$$$ converting, cutting away, or replacing rusted material only to have it reappear within a few short years. So don't purchase anything with rust.
Good luck and happy trails to you!