cameras

I'm looking for any advice/experience on deploying these guys. There are four of them to be deployed around a large shop. So far the only hardware we have is the cameras. 2 are replacing existing old cameras and 2 are new locations. I understand I'll need a PoE switch; 4 port required but...

Anyone have a recommendation for a video camera installer for a commercial client of mine in the North Hollywood area of los Angeles. It would be 20 camera install (interior and exterior). They are currently using D-Link cameras, but they are crappy and difficult for the client to manage...