Ther is anot a better pistol that you can conceal no matter what you are wearing than a Kel Tec P3at 380. A shotgun is the ultimate home defense weapon. even an inexperienced shooter can grab a shotgun and point in the general direction. If you are looking for home protection and don't have more than $200 then you should consider the shotgun approach. Not many even cheap pistols for $200 or less out there. If you are dead set on not using a shotgun then you should probably consider a bat. It is closer to your price range and if you are inexperienced you will probably more effective.
This idea can get you killed. Shotgun pattern sizes at social distances are much smaller than generally believed. Aiming, or at least precise pointing, is not optional. A few years ago a nutcase firebombed a neighbor's house in, i think, Yukon. I met the victim at H&H while he was shopping for some home protection. He said he had fired his one shotshell at the guy, who was standing in the front yard, and missed. He assumed a wide pattern, when at the distance he fired, the actual pattern was probably about three inches.
If you doubt this, hang some targets at five, ten, and fifteen feet, shoot 'em with any shotty, and prepare to be surprised at how close together all the shot still are at those distances. CB