Cash in on find (6)
I believe the answer is:
redeem
'cash in' is the definition.
(redeeming is a kind of cashing in)
'on find' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'find' becomes 'deem' (both can mean to judge or perceive to be).
're'+'deem'='REDEEM'
(Other definitions for redeem that I've seen before include "Save from sins or buy back" , "Make amends (for)" , "Avoid pawn loss" , "Make good" , "Claim back" .)