If you organize and lead trips, you will need to take ownership of a Montana......you can save waypoints and tracks; you can create routes and save them. You will also have the option of "birdeye's" view, where you can subscribe to the service and get a birdeye's view of the area you are in high definition. The Montana, given its capabilities, is an expensive unit but a real must for active Marshals.
Alternatively, you can use any kind of navigation unit that allows the input and saving of waypoints. Good luck on your choice.