The only one I can think of off the top of my head is called Grace Can Lead Us Home by Kevin Nye. It's grounded in Left Christian theology though. It basically focuses on housing-first initiatives and how they actually work. I'd like to find more secular texts to add to my list so I'm gonna come back to this later and see if others have suggested anything.

Tangential but I saw this posted in the anarchy comm yesterday: https://theanarchistlibrary.org/library/anarchist-teapot-mobile-kitchen-the-anarchist-teapot-mobile-kitchen-s-guide-to-feeding-the-mass#toc32

Could be relevant too.

Do some searching on the organizations DULF (Drug Users Liberation Front) and VANDU both on the downtown East side in Vancouver BC. They've been involved in things like mass resisting camp sweeps and fighting legal battles to get addicts access to safe injection sites and safer supply, and many other things. VANDU was a key player in organizing the unhoused community to protest and resist displacement of the whole neighborhood ahead of the winter Olympics. It was a huge thing.

There's a podcast called Crackdown you may find interesting as well. Garth who hosts has been in VANDU a long time and does incredibly good work.

I don't have much in terms of literature, but this post reminded me of the time the IWW helped organize a "panhandlers union" in Ottawa: https://en.wikipedia.org/wiki/Ottawa_Panhandlers%27_Union