There are a few things that can legally be done to put the odds in your favor.

One is instead of simply turning on normal room lights turn on extremely bright and powerful lights that will temporarily blind who ever is invading. And if the lights are mounted on the four walls facing toward the center of the room they will blind anyone who has just entered from the dark, and if they are using night vision then well guess what.

Another thing is to use multiple high power photo strobes and if they are combined with very loud sound effects like a machine gun or gun battle played though large speakers powered by a rock band type amplifier that can be the Citizen's flash bang.

Cops have and use Flash Bangs so why can't us Citizens have and use our own versions.

There are also a lot of other things that can be done to make any invader wish they had not invaded like if you have hard floors and not carpets dumping a large number of marbles on the floor can really mess up any group of invaders. Also spraying oil on the floor or setting off Tear Gas or even just smoke canisters can really cause problems for any invaders.

Even having strategically placed mirrors can cause problems.

Anything you as the victim can do to slow down or confuse the invaders gives you an advantage over them.

And if you really want to have fun just combine several of the things I mentioned.

Think of what would happen if the invaders had strobes go off, and then marbles all over the floor and then tear gas went off. And if you had some mirrors they might even shoot each other.

I love watching movies and I think that a lot can be learned from movies.

Take the Movie FX for instance.

The good guy used movie Special Effects to take out the Bad Guys. One thing he did was set up a mirror that caused one Bad Guy to Shoot another Bad Guy by mistake.

And think of what would might happen if a person had a life size photo made of their self pointing a pistol and that was mounted on a wall of a room and when anyone entered the room the lights turned on and the invader saw what he thought was you pointing a gun at him.

The idea is to cause as much confusion as possible and if the invaders are falling all over the place because of steeping on marbles they are so out of luck. And are at the homeowners mercy.

And since none of this is designed to kill or harm it is all legal.

And to counteract the invaders cutting off the power, just use multiple 12 volt Auto Batteries connected to an Inverter. The lights do not have to stay on for very long a couple of minutes will more then suffice.