First, self defense is in the mind,not in the holster. I urge you to get a Ginsu knife out of the drawer and stick it in your pants right now. Bring the chainsaw inside assuming you have one in the garage, and place it beside your chair. You will feel a lot better!
Seriously, I keep a full magazine on my defensive weapons. These include six shotguns and several handguns for carry. Past that, I keep approximately 100-200 rounds of buckshot on hand for those HD shotguns if needed, as well as the same amount in SD ammo in .45ACP and .38 Special. On top of that I keep about 400 rounds each of target ammo in 45, 38, 9mm, 357, 7.63X36, then about 6-10 boxes of bulk pack .22 ammo. I do that to keep myself from running to the store.