Sell that thing

Buy couple of small or tiny cameras for a notebook, the smaller the better. From Sony VIAO usually smallest.
They are USB. So you can connect them with a quality USB 2.0 4.5 meter cable to an old notebook.
Using Xeoma software, which is free and paid, depending on version, you have yourself a video surveilance system.
Now keep in mind, you can make that cameras looking like a regular cable, so they are hidden, plus your notebook has a battery, so no power outtages can disable it, and also you can mess with camera filters and make them night vision.