It’s small matter to accept some money arbitrarily (2,6)
I believe the answer is:
at random
'money arbitrarily' is the definition.
I can't judge whether this definition defines the answer.
'it's small matter to accept some' is the wordplay.
'it' becomes ''t' (abbreviation. e.g. in 'tis).
'small matter' becomes 'random' (I can't explain this - if you can you should give a lot more credence to this answer).
'to' says to put letters next to each other (I've seen this in other clues).
'some' says to take the initial letters.
The first letter of 'accept' is 'a'.
't'+'random'='trandom'
'trandom' after 'a' is 'AT RANDOM'.
Can you help me to learn more?
(Other definitions for at random that I've seen before include "willy-nilly" , "Indiscriminately" , "In no prearranged order" , "Casually" , "Haphazard" .)