One other thought. At times you will be in close quarters. A cheap pair of two way radios comes in handy. Your ground guide can talk you in rather than misunderstanding hand signals.
totally off topic here, but whenever my kids go out "hunting" or whatever, running around the back 40 i make em take some 2 ways, that way i can check in with em, or they cal holler at me if they get into it with some coyotes or what not