I see you have a lot of questions. Unfortunately, I don't have the time to answer them. It seems, however, you may be interested in finding them and you're not arguing in bad faith. If that's the case, I'd search for those answers from someone more knowledgeable than myself. Most of your questions are "who pays for it" and the answer is simple: we all do. We are already (most of us) paying for housing. What if we took away the investment aspect of it? Prices drop.

It shouldn't be a commodity and it should be a human right to be housed.

The other questions are about what to do with all the other properties. Well, I'm not sure. But, if you own the home you're living in then nothing should change. If you own 500 homes, then too bad.