rent-a-
prefix
denoting a rental service
derogatory. or facetious. denoting a person or group that performs a function as if hired from a rental service
⇒ 
rent-a-mob
rent-a-
                combining form
     -          often humorous denoting availability for hire of a specified thing〈常幽默〉表示“某物可租用”:
-       rent-a-car rent-a-crowd.