Re: What do you call this person?
Just to clarify, the idea of being homeless because you have become desitute and lost your home has never been romantic. That's just sad. But there is a romantacized notion that there was a time when there were people with no fixed addess, who hopped on trains (illegally) to take them from one spot to another, sitting around campfire at night with others who did the same thing, and while they had no money they had their freedom, etc. Those are the types of people you might refer to as hobos.
I have never, not once, seen an unfortunate person on the street and heard someone say "We should do something about/for the hobos" or "I was shocked to find a hobo using the bathroom in our office building."
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.