I installed an inexpensive rear view camera. Works great for keeping an eye on the Toad and anything coming up behind or beside me.
Rear View Camera | 2001 Coachmen Mirada 300QB
As for the wireless - I originally installed a cheap wireless transmitter and receiver for the camera, and got power to the camera and transmitter via the MH running lights. I since rewired to a separate switch and ran a cable back to the camera so its no longer wireless, and no longer depends on running lights being on.
My wireless camera was interfering with my Tire Pressure Monitoring. I installed TPMS in the rear tires of my Camry and the two Tow dolly tires. I discovered the Wireless rear camera was interfering with the TPMS transmitters. That was one of the main reasons I decided to hard wire the rear camera and do away with the wireless.