Yeah, post weirds me out a bit as well.
Cheapest I'd go in a handgun is 200 dollar range for a former eastern block 9mm Mak firing service gun. PA63, CZ, whatever. They're all reliable. I picked up a Polish Radom P64 from Gander Mountain a month or so ago for $199, but you can find 'em for a bit less online. You'd have to pay FFL charges and shipping if ordered, though. They're very nice little weapons and I'm sorta really gettin' off to mine even though it's really just a glorified .380. It's very accurate and ammo is cheap and available, something you can't say for .380 at the moment. The P64 is very PPKish, all steel, 100 percent reliable, and very accurate.
I really can't think of any other handguns than the various eastern block Maks that I'd rely upon that are under 200 bucks unless, maybe, you found a Tokarev. I had a couple of 9x19 Norinco toks 15 years back. I much prefer the Maks. Most toks are in 7.62x25 which is a bit hard to find except for online and I don't know that anything is available in a hollow point. 9mm Mak is even available in defensive loads by Hornady and Glasier makes frangibles. I'm carrying imported Silver Bear JHP, though, 12 bucks a box of 50.
Next step up in price for acceptable defensive handguns for ME is around 300 bucks. You can find the various Kel Tec type .380s and subcompact 9s in that price range from Ruger, Taurus, Kel Tec, etc. There are still trade in .38 revolvers, M10 Smiths and the like, to be had as well as Rossi revolvers. Rossi .38s are well under 300 at Academy. But, 100 dollars is just too restrictive. Yeah, before I went that route, I'd find an H&R single shot shotgun. At least they're reliable and with practice and a butt cuff, you can do some amazing things if you get good with one. You can make one sound like a pump, at least for the first couple of shots, with enough practice.