Cheers Stew, this is my next course of action, I will be wiring in an alarm with the PIR with a high decibel output, lets wake the whole street up and someone may actually see him running away from our property....
Maybe best to install some kind of cat deterrent first incase they set them off all the time!
It's amazing what light will do to deter people.
If he was young you could have installed a 'mosquito' as it actually hurts 'young' ears. I'm affected by it too but it's only meant to be teens that can hear it. They were installed at the train station in Aberdeen to stop kids hanging about!