Cash put up will be invested in church (6)
I believe the answer is:
change
'cash' is the definition.
(I know that change is a type of cash)
'be invested in church' is the wordplay.
'be' becomes 'hang' (hanging is a kind of being).
'invested in' indicates putting letters inside.
'church' becomes 'ce' (abbreviation for Church of England).
'hang' going into 'ce' is 'CHANGE'.
'put up will' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for change that I've seen before include "Coins of low value" , "protean" , "Alter for small coins" , "It may be small" , "Coppers, perhaps" .)