There's lots of options. When I had my Tundra with a 27' Winnebago Minnie, I bought a Rear View Safety wireless camera system. Just having one rear view camera was all I really needed. The system was capable of operating multiple cameras. Having a camera mounted on the rear of the truck would have been handy for hitching up without a worthy assistant. I didn't feel the need for side view cameras, but if I were towing some of these very long trailers I see on the road now, it would probably be very handy.
And, the wireless worked fairly well but I did get interference now and then. Supposedly, the newer systems are much better. And, I wired the camera into the running lights which enabled me to use the camera anytime just by turning on parking or headlights. If you have the skill set, I'd go for a wired system....I just didn't want to tackle the job nor pay $$ to have it done!