"What a ___!" ("It's a bargain!") (5)
I believe the answer is:
steal
'what a it's a bargain' is the definition.
('steal' can be a synonym of 'bargain')
This is the entire clue.
(Other definitions for steal that I've seen before include "crib" , "Take without permission" , "bag" , "Appropriate" , "Rob" .)