For starters you want :
Night time vision.
Colour camera/s - Not Black & White.
Auto On/Off recording.
Hard drive recording system - Not tapes.
Place the camera's in a not too visible place and well out of reach.
Maplins do a good range...http://www.maplin.co.uk/productsearch?criteria=cctvhttp://www.maplin.co.uk/productsearch?c ... ctv+camera
We have a wired system on our house and the quality is like watching normal tv right up until 400 yards away,
so don't go for any cheap crap as you'll only regret when the 'see' the culpret on the screen but thats it!
Its a person and you can't even make them out due to the shite clarity of the camera.
Our hard drive system can be viewed on our TV screen which has six split screens and all six cameras
can record independently, comes with a mouse for quick on screen use and a remote to record, also
the hard drive can be edited on to make you aware that any one camera has been activated and has
started to record, this is a bloody good thing as you can catch any fookers in on the act, instead
of finding out the next day you had intruders, saves time looking through the card.