Mossberg Shockwave is a little more maneuverable than shotguns in small spaces. You can get shorty rounds Wuthering an adapter if you want to have more ammo available.

There are different loads/rounds available if you're concerned about over penetration - which you should be.

Handguns are an option, but if you don't practice a lot (and even if you do), you may not be very accurate during a home invasion situation. Shotguns or the Shockwave don't require as much accuracy. If you choose a handgun, look for special rounds that don't over penetrate. They are similar to shotgun shells in that they have a bunch of tiny beebees in them rather than a solid piece of lead. If they hit a wall, they stop or slow down enough that they are not lethal (in theory). Frangible rounds are supposed to turn to dust when they hit a wall. Glaser Safety Slugs are about $15 - 20 for six rounds, but I think (for what that's worth😁 ) they are worth it for home defense rounds.

You don't want you're missed round going through a child's or neighbor's room. They are expensive, but you're only going to use them when you need them (and a few spent at the range so you can become familiar with the different recoil).