Teledoorbell is pretty much it. I've installed a few of them. You just need a run of cat5 to the doorbell location,

teledoorbell

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You would run coax cable and a pair of conductors to each camera you can send power to it, and get video from it. Usually we use RG59 and an 18g pair of wires.

RG59

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Power over Ethernet (PoE) Adapters can be found cheap on line ~$20

CCTV

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