Money reportedly in secret store (5)
I believe the answer is:
cache
'secret store' is the definition.
(I've seen this before)
'money reportedly' is the wordplay.
'money' becomes 'cash' (I've seen this before).
'reportedly' shows a homophone (sound like).
'cash' is a homophone of 'CACHE'.
'in' is the link.
(Other definitions for cache that I've seen before include "memory" , "Secret store of valuables" , "Treasury" , "Hidden store of things" , "Concealed store" .)