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Video-
You can get get 4 cameras running on 1 network cable, as there are 4 twisted pairs and each camera only needs 2. You could set up the network cable running between the cameras in a 'daisychain like' configuration, terminating the cable at the first camera, with 75ohm balun for that camera coming form 2 wires, and a network socket for the pass through of the 6 remaining wires. You continue the cable run from the first camera doing the same for the remaining cameras.
Then 'daisy chain' up a cable for power. If cameras are 24V, you could have 3 cameras plus power on the cable. If you were using motorised devices then I think you need a separate thicker gauge wire, as even my little panasonic dome uses 15w, so 4 cameras is 60w, that's 24V-ac at 2.5amps which would not give you much distance at all (I think).