I'd prove a vagrant is given too much (8)
I believe the answer is:
overpaid
'given too much' is the definition.
(I've seen this before)
'i'd prove a vagrant' is the wordplay.
'vagrant' indicates anagramming the letters (I've seen this in other clues).
'id'+'prove'+'a'='idprovea'
'idprovea' anagrammed gives 'OVERPAID'.
'is' acts as a link.
(Other definitions for overpaid that I've seen before include "Rewarded too well" , "Handed over too much money" , "Too highly rewarded" , "Having salary in excess of one's worth" , "excessively remunerated" .)