Money in this, tied up, reportedly (5)
I believe the answer is:
trust
'money in this' is the definition.
(as in a trust fund)
'tied up reportedly' is the wordplay.
'tied up' becomes 'trussed' ('truss' can be a synonym of 'tie up').
'reportedly' indicates a 'sounds like' (homophone) clue.
'trussed' sounds like 'TRUST'.
(Other definitions for trust that I've seen before include "Firm belief (in a thing)" , "Firm belief (in another)" , "Firm belief (in person)" , "Faith - guardianship - after 10, the owners of the Guardian" , "Have faith or confidence in reliability of" .)