It really depends on your organization, and what you want to use it for.
here are some questions to consider:
1) who is going to staff it? does it have dedicated staffing, staffed by off duty/recalled personnel, or administrative personnel?
2) Where should it be used? just within your primary area, or is it available to the surrounding areas?
3) what type of equipment does it have, how many patients can it transport, and how do you get people inside?
4) what do YOU want to use it for? Do you want to use it simply to transport a lot of people, use it for rehab, or use it as a command post for large preplanned incidents?
In most agencies I am familiar with, what those buses are designed for (a very small subsection of overall EMS calls) and what they are actually used for are very different.
