Value in financial institution maintaining good bonus? Force to change (4,3,4,4)

I believe the answer is:

bang for ones buck

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'value' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'financial institution maintaining good bonus? force to change' is the wordplay.
'financial institution' becomes 'bank' (bank is a kind of financial institution).
'maintaining' indicates putting letters inside (inserted letters are held or maintained).
'good' becomes 'g' (abbreviation).
'to change' indicates an anagram.
'g'+'bonus'+'force'='gbonusforce'
'gbonusforce' with letters rearranged gives 'gforonesbuc'.
'bank' enclosing 'gforonesbuc' is 'BANG FOR ONES BUCK'.

'in' acts as a link.

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I've seen this clue in The Guardian.

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