The above answers are good. "I'll have the money I owe you by next Monday!!" "You better hope so, or I'll . . ." Oftentimes, colloquially, the "so" is omitted. "You better hope" is perhaps an abbreviation of "you better hope that it is so" or "you better hope that it turns out this way." As already mentioned, the context is sometimes in the context of force or adverse consequences. Best wishes for you studies.