A standing charge (7,3)

I believe the answer is:

parking fee

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

'standing charge' is the wordplay.
'standing' becomes 'parking' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'charge' becomes 'fee' (fee is a kind of charge).
'parking'+'fee'='PARKING FEE'

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I've seen this clue in the Evening Standard.

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