Marks account with small amounts of money (7)
I believe the answer is:
accents
'marks' is the definition.
(accent is a kind of mark)
'account with small amounts of money' is the wordplay.
'account' becomes 'acc'.
'with' is a charade indicator (letters next to each other).
'small amounts of money' becomes 'ents' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'acc'+'ents'='ACCENTS'
Can you help me to learn more?
(Other definitions for accents that I've seen before include "Local ways of speaking" , "graves?" , "Strongly contrasting details" , "Brogues" , "eg Circumflexes" .)