Charters are easy on the environment.
You decide where you want them to go and for how long. Make sure that the tours you are developing are accessible by the vehicle that is expecting to take the tour. However, smaller mini-buses or vans probably will be able to make the trip. If the tour includes a drive through a park, make sure that the motorcoach can maneuver safely, park if need be, or make an easy turn-around. Do not put motorcoaches in the position of having to back up.