Parties hard for money (4)
I believe the answer is:
dosh
'money' is the definition.
(I've seen this before)
'parties hard' is the wordplay.
'parties' becomes 'dos' (do is a kind of party).
'hard' becomes 'h'.
'dos'+'h'='DOSH'
'for' acts as a link.
(Other definitions for dosh that I've seen before include "Ready" , "Money (sl.)" , "Lolly (slang)" , "Bread - gravy - dough" , "Moolah (slang)" .)