Install an alarm system in your home. Even if it was just local, a noise maker tied to every entry point would have spoiled a lot of the historically significant crimes that are being studied today.

This isn't a perfect solution, but most criminals care about being caught. Do everything you can to bring attention to them and you'll be more likely to win.

I'm in the US, so being armed and trained is a part of that. But you can't defend against what you don't know is there and making a bunch of noise is almost always going to be in your favor.

Peace.