[45Gunner]

Living in close quarters with thin walls, surrounded by residents in similar situations would present a unique situation, I would think. I am trying to understand your points of view. If your go to gun is a shotgun, are we assuming a band of rogue BG's or a single intruder?

If you are dealing with a single intruder, would you not be worried about "collateral damage" or accidently killing the neighbor in the adjoining apartment? However, if you had a full frontal attack by a mob of intruders, then I would agree that the shotgun would be the way to go and that their bodies would most likely prevent anything else from penetrating thin walls.

Without knowing the statistics, I would guess that most break-in's are committed by one or two individuals. It tight quarters, as described, I would be inclined to go with something that offers ease of handling, has take down power, and yet will not kill a resident in an adjoining apartment. I think a pistol loaded with hollow point may be my first choice as I think it would give me the ability to seek cover behind a piece of furniture and offer more opportunities in the way I could discharge the gun, if it came to that. And, if it misses the target, it will cause damage to the wall, reducing the risk of accidently taking out a neighbor.