My brother is likely homeless in Austin right now. Not totally sure... sometimes my mother gives him money or pays for an extended stay motel. He is mentally ill (no diagnosis but probably bipolar or schizoid), a drug user, and did 11 years in prison. He had a condo my parents bought him in the 90s. He sold it 3 years ago without telling us, and has pretty much spent down the 90k proceeds (it was a dump).
My solution/theory: What this country (and Austin) needs are cheap cinder block single room occupies like the tenements that existed in NYC in the early 20th century. If the rent was ~600 and we just needed to give him money for rent and food, I could swing it on his behalf. I cannot swing $2.5k/mo to keep a roof over his head. He is too obnoxious to live with me or my mom or really any roommate. I'm tempted to find a shack or rv in the country to lease, but he has no car. I could probably convince my mom to buy him a wagon or van or whatever, but a decent one is like $20k and he has no license. He also refuses my free phone.
Anyway. It sucks. It is very hard to help some people, especially those who don't really want help.