Howard Phillips

If you're using IP cameras there are a few options; A NUC or Rasbery Pi can run VLC player which can display streams from some cameras (depending upon if the camera has RTSP capability and its codec). You can run 4 VLC players simultaneously in windows, but getting the machine to boot unattended and having the 4 separate instances of VLC be where you want might be tricky (but 'free' (not counting your time)). There are boxes which will display quad views of IP cameras such as the GV-IP decode box. These are handy little devices if you only need to view a limited number of cameras because they connect directly to the output stream of the cameras (no archive or search capabilities) and can cost less than a station license from the larger NVR manufacturers. KVM extenders, allow you to take the Keyboard, Video, and Mouse output of a DVR and extend it hundreds of feet, usually over cat 5x or cat 6 cable. You don't need to have the keyboard and mouse at the far end, but you will have to unplug it and plug in a local monitor at the DVR/NVR when you need to work on it. I am sure there are a couple of other options but those are the quick ones that come to my mind.