Possible Clues:

• Keeping buff?
• Collector of useless items
• One who has trouble letting things go?
• Rodent that accumulates a bunch of stuff in its nest
• American hoarder of Sinatra, F and chums, so to speak?
• Compulsive hoarder
• *Noted Vegas entertainers of the 1960s
• Collector of unnecessary things
• Sinatra, Martin & Co's gang slightly mixed up by an American collector?
• Collecting rodent