need advise, which drink machine will be best for a martial arts school?

[mizugori]

There is currently a powerade machine in place, it is poorly maintained, I talked to the owner of the school and he is interested in switching vendors but which machine and product should I try to put in there? If I wanted to just replace it with an identical powerade machine, where could I buy one of those? (I'd prefer to go new, as I want it to have a service contract so if it breaks the company will come fix it promptly.)

Or, what might be a better idea? I thought about vitamin water, but again I cannot seem to find where vitamin water vending machines can even be bought... does anyone know?

Thanks!