Running the camera on the sewer lines

I’m doing my due diligence on a couple of parks right now.  When I run cameras down the sewer lines do I do it on the main lines and branch lines or should I be running the cameras from each lot as well?  

Also, Roto-Rooter is a lot cheaper to use than a plumber but I’m guessing their service isn’t as good as a top notch plumber.  Should I be using a plumber instead to ensure high quality work for running these cameras?  

Roto-Rooter is as good as any plumber – even better in some cases. You only run the camera on the main line.