One's occupation may depend on paying it (4)
I believe the answer is:
rent
'one's occupation' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'depend on paying it' is the wordplay.
I cannot really see how this works, but
'on' could be 're' ('on' can be mean 'with reference to') and 're' is present in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is located in the answer.
A single letter 'n' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'may' acts as a link.
Can you help me to learn more?
(Other definitions for rent that I've seen before include "Payment for lodging etc" , "Tear; hire fee" , "One due a letter" , "slashed" , "Regular payment" .)