for the house warren, you want a pair of dobermans, proper guard dogs, my mates boss has 2, doesn't even lock his house when they are in, they've seen off anyone thats not welcome, plus if you are in, they will hear anything before you will, so they will get you up if anything is wrong.

and get some cctv up, and wire it in to a hard drive recorder, easy to maintain then instead of swapping tapes all the time, then at least you can see who it is and pass it on to plod as evidence