re: 3 corporations now own 19,000 metro Atlanta homes

There are laws being proposed to prevent, mitigate this. One of them I've heard about will prevent corporations from purchasing a home the first 30 days on the market. That should help. Here's some other info:

Some Texan media outlet on legislation to limit institutional purchase of SFH

But of course, our Congress is ineffective, so nothing will happen to help average Americans.