Realtor's goal (4)
I believe the answer is:
'realtor's goal' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sale that I've seen before include "Cut-price offer" , "Auction; Cheshire town" , "Period of reduced prices" , "Auction - somewhere in Greater Manchester" , "Bargain time" .)