I understand the desire for a semi auto, but for practial application, a nice pump works just fine. You can get a decent one plus the extras for well under $300, and for less than a full scale military op, it will serve you just as well.
Bonus: That sound of loading a round is truly chilling to a perp. They will run away just from hearing it. Trust me on this, I’ve been there.
I have a Winchester 1300, 8 shot pump. Pretty sweet. I think I paid 350 for it.
My Remington 870 fills the bill for me; the slide makes a big noise in the middle of the night.