Our parents died leaving my sister and me to take care of our brother. We are getting older. Life is short. Our oldest brother died. I'm trying to figure out the next steps. We have been doing this for over four years. We are not wealthy. He is on Medicare and Medicaid.
Call your County Disabilities Dept. I was able to get my nephew in a State program. I would not go for guardianship. Very hard to revoke once you have it. I may allow the State to take over his care requesting he remain near family. He does have my daughter as a back up POA if something happens to me. But if he starts showing Dementia signs, which can happen with his neurological problem, I will probably allow the State to take over his care. I am 76 now. I have already told my daughters I don't expect them to care for him.
https://thearc.org/find-a-chapter/
Did your brother have a social worker or other agency staff member who helped him with his Medicare and Medicaid, and any other services? You can check back with that person or people. The info might be in paperwork that your parents had. Did they leave any financial provisions for him?
The systems vary by state but there should be some assistance in place that he can access. Did your parents have your brother at home with them? I've known a couple of people, one in particular, who really thrived once they moved into group homes, with professional staff to help them live independent lives, and peers as friends, along with social and household activities.