If the cameras are IP based they connect directly to the network at home. They do not have "local recording". You need to set up a computer somewhere to be a server – or set up an account with a fee-based service – to store all the video or stills it takes so you can get to that data.

If the cameras are analog, they can plug into a DVR. The Digital Video Recorder has a built-in hard drive or it can be a computer set up with a DVR card. This needs to be ON all the time. The DVR or the computer will get assigned an IP address for remote access. It becomes a part of the network.

You did not tell us:

Do you need outdoor coverage?

Do you need the camera to have night vision?

Do you need the camera to have pan/tilt/zoom capabilities that can be remotely controlled?

How long does the video need to be stored?

Can a still every few seconds do what you want or do you really need real-time video?

What are you expecting to see?

Do you need audio (some surveillance cameras include a mic).

How are you getting the wires from the camer to the DVR?

"Wireless" is not actually wireless. "Wireless" surveillance cameras send the video image wirelessly to the receiver/base station – the camera still needs power (wires) and the basestation needs wires for power and for connecting to the DVR (or computer equipped with a DVR card)…

Swann, Lorex and Q-See make affordable consumer-grade surveillance equipment.

For 3 cameras simultaneously, but sure whatever system you get has "Quad-Splitter" capabilities. Since you want 3 camera views, you might as well go for 4 cameras – that is the smallest multi-channel quad-splitter "size".

Higher resolution and more feature rich cameras will cost more. I use wired Swann and Lorex outdoor-rated cameras with night vision (up to 70 feet away). I think Fry’s carries them for $150 each. One of the 4-channel DVRs I use is from Lorex. It has a 250 gig drive and can store up to 30 days of video.
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