I carry a 12 ga. pump shotgun with a short pistol grip stock. It is called a "snake charmer" Is short enough that I have a vertical mount in the bedroom shirt closet to hold it. I also have a trigger lock on it for safety, with the ammo stored in another location. (just the thought of a child stumbling across it scares me) The gun is out of sight, and difficult to find if you don't know it's location.
I have been told by several police officers that just the sound of a pump shotgun being cocked will scare off 99% of thieves. So I will try that first.