Hammacher Sclemmer sells two fake cameras for $60. For that much you can setup your own security system with a low-end web-cam hooked up to a PC. It is completely fake and even includes a blinking red light powered by a AA battery to really convince criminals that they are being recorded. Or if you are really cheapjust do what I do and put up a fake sticker: “Monitored by Such&Such” You receive two of these faux cameras for a blistering $60.”]
Source: https://gizmodo.com/fake-security-cam-scares-the-baddies-235202