I got the costco setup too. The new dvr can be monitored from a smart phone, if that helps you any. The night vision isn't the best, but for the price, you can't go wrong.
As far as the 12ga; I'd personally go less than lethal: Just stake out with a pellet gun, and nick the little gangsta in the forehead a few times...more fun to watch him cry, than to bleed all over your new truck