Outlet for posh model (4)
I believe the answer is:
shop
'outlet' is the definition.
(shop is a kind of outlet)
'posh model' is the wordplay.
'model' indicates an anagram.
'posh' anagrammed gives 'SHOP'.
'for' is the link.
(Other definitions for shop that I've seen before include "Inform on (slang)" , "Store or boutique" , "Betray - place selling things" , "Be disloyal to" , "Store - betray" .)