Very low cost backup-camera using WiFi cameras?

DFord wrote:
The camera needs to be able to send a "mirror image" of the view behind you or you'll be all screwed up looking at the picture.

I used a baby monitor in my first RV as a rear view camera system and it was disconcerting to see those vehicles on the screen coming up my right/shoulder side. ;)
somebody here told me I could switch two wires but never got the nerve.
bumpy