Money perfect to be invested in lavish project funding (5-2-3)
I believe the answer is:
grant-in-aid
'lavish project funding' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'money perfect to be invested in' is the wordplay.
'money' becomes 'tin' (I've seen this before).
'perfect' becomes 'ai' (I've seen this in other clues).
'to be invested' becomes 'grand' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in' is an insertion indicator.
'tin'+'ai'='tinai'
'tinai' put inside 'grand' is 'GRANT-IN-AID'.
Can you help me to learn more?
(Another definition for grant-in-aid that I've seen is " Money given, eg, to local government".)