Guns are an expensive hobby. You'll want to have several different nice guns, and lots of ammo, and some targets, and a safe, and time at the range. It's easy to spend thousands a year.

If you just want a gun for self defense or murder, they are cheap. Buy a Hi-Point or a Ruger LCP for $175 and a box of 50 9mm and now you can kill more people than you'd ever have a reason to.