What is a cheap way to set up a security camera in my car?

Question

I own a small taxi cab co. and I want to install security cameras in my cabs (with night vision if possible). Sound would help also.

Answer 1

Walmart has a rearview camera for the car for only 99 dollars.
It has a 3.5 inch color display and all wiring inlcuded with a small cam.It is surprisingly good quality camera and color display.