That chap's a bit of a chiseller! (3)
I believe the answer is:
his
'that chap's a bit' is the definition.
I can't judge whether this definition defines the answer.
'of a chiseller' is the wordplay.
'of' indicates the answer is hidden within the clue.
'HIS' is hidden within 'chiseller'.
Can you help me to learn more?
(Other definitions for his that I've seen before include "That man's" , "that chap's" , "Belonging to the male" , "It belongs to him" , "To - Coy Mistress (Marvell)" .)