We have a system that was bought from Maplin. Think it was about £200 but hubby bought it not me. It has 3 cameras, but you can add more, add it records really clearly even when it's dark (we have rabbits and foxes in our garden at night). Hubby spent a couple of evenings putting up the cameras, and positioning them right, and the wires go up behind the fascia board, accross the loft and down some tracking to the desk in the corner of the bedroom. The system comes with a box that can record from the cameras, can't remember how many hours, but I know it will cover a weeks holiday, and hubby has attached a monitor to it to watch. I believe we could set it up to view it over the internet, and hubby also mention motion sensitive. The staff in Maplins are really knowledgeable and helpful with it.