One can make fine distinctions between them.
"Bums" are homeless people who hang around one primary location.
A "deadbeat" is someone who does make good on his financial obligations. He may live in a penthouse apartment, but he doesn't pay his, e.g., court-ordered child support.
A "vagrant" (from the Latin vagārī ("to roam, wander)" is a "bum on the move."
A "vagabond" (same root as "vagrant") is a term with romantic connotations, referring to a traveller or perhaps even fortune-seeker who moves constantly from place to place.
A "hobo" has a strictly American etymology, and originally referred to itinerant agricultural workers or farm laborers who were "down on their luck."
A "pan-handler" is anyone who begs in public.
Please feel free to add to the list!
Maybe we should re-institutionalize the honorable profession of "beggar" - as it was in the Middle Ages! Cities used to allow begging - but only if the beggar had first been officially registered as "needy."
Regards,
“Debtor in possession”? /s