Having bought, though about a quarter is on credit (6)
I believe the answer is:
owning
'having' is the definition.
('own' can be a synonym of 'have')
'bought though about a quarter is on credit' is the wordplay.
I cannot quite see how this works, but
'quarter' could be 'w' and 'w' is found within the answer.
'about' could be 'on' (as in a book 'on' a certain topic) and 'on' is present in the remaining letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for owning that I've seen before include "Possessing" , "In legal possession of" , "Admitting" , "Being in possession or confessing" , "Conceding - possession" .)