Definitely need more than two. I have one hidden in every room of my house, except my bedroom where I have a shotgun and a 38 special. Those 2 are for a potential rapist. The others are for burglars. LOL I'm very well organized. I'm very well armed. 8-)
Smart. Nothing deters crime quite like a shotgun -- that big hole at the end of the barrel is a frightening sight. Sometimes stupid (or drugged up) perps might regard someone with a handgun - especially a small one, held by a woman - lightly enough to attempt the crime anyway, and you might end up shooting and fighting with him. Not a desirable circumstance, to say the least. But shotguns sober BGs into complacency, most of the time.
Only problem with a shotgun is that it can much more easily be grabbed away from you than a handgun, especially if you're looking for the intruder. That's why it's always wise to carry a backup handgun (like your .38 Spl) when you're wielding the shotgun. In the event that a perp attempts to grab the shotgun away from you, you should be able to quickly draw that .38 with one hand and unload on him before he can turn the long gun on you. It's definitely something one should practice.
....But you probably know all this. Sounds indeed like you're well prepared and well armed :)
Stay safe!