So I'm looking at buying a shotgun to enhance my home defense situation. My mind immediatlely goes to a 12ga, pump action, 18 inch barrel. Any advice for a home defense shotgun is welcome. My price range limits me a lot, under 400(300 would be ideal) I've seen for that price range the remington 870express and a charles daly model. Advice on guage, barrel length, action, brand, etc.