|i work in the security industry, and it all really depends on what you are wanting covered.|
for starters, you could have 4 PTZ (pan tilt zoom) located at each corner, have them programmed to 'tour' which basically means you point a camera in a certain direction, save its position and continue doing that until that camera has maybe 6 or 7 areas its looking at.
in the office you could have a static wide angle camera, or maybe a couple of 360° ceiling mounted cameras (these can also be covert if needed) again, these can be PTZ type or static.
everything really depends on what you're actually wanting the cameras to do, obviously the more you want, the more it costs, and if you have security monitoring them during the day/night, or if you want Ip cameras where you can monitor remotely from any pc, laptop or smartphone
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