Revolutionary upmarket housing swindle (4)
I believe the answer is:
ramp
'swindle' is the definition.
(I've seen this before)
'revolutionary upmarket housing' is the wordplay.
'revolutionary' says the letters should be written in reverse.
'housing' indicates a hidden word (part of the clue houses the answer).
'pmar' is hidden within 'upmarket'.
'pmar' written backwards gives 'RAMP'.
(Other definitions for ramp that I've seen before include "One with an inclination" , "Sloping surface; swindle" , "cheat" , "Incline" , "Change of level in road" .)