My Opinion, is much simpler these days:

-Every house should at least have a basic Mossberg 500 or Remington 870 12gauge.

-Every house should at least have 100-200 rounds of bird shot and a couple boxes of slugs.

A 12gauge can provide protection, and also be a great tool to get birds/fish/rabbits/deer/bear, basically anything that moves in North America, with the proper ammo.

Guns hold onto resale value pretty well, especially un-shot. Purchase the above and hide them in your house to hopefully collect dust.

They were right, "change" is coming.