Please don't forget about the Salvation Army. They have a free rehabilitation service and can provide him a bed and food in exchange for working. Some work in their store, other sort, repair or clean donations getting them ready for sale. Sure, he'd have rules to follow, but it's better than living on the street.
http://www.satruck.org/search-arc
Click on that link, enter your zip code or City/State and it will generate a list of SA Rehabilitation Centers closest to your area.