Performed hip-hop in street raising money to offer poor (8,3,4)
I believe the answer is:
strapped for cash
'poor' is the definition.
(strapped for cash means very poor)
'performed hip-hop in street raising money' is the wordplay.
'performed hip-hop' becomes 'rapped' (hip-hop often features rap).
'in' indicates putting letters inside.
'street' becomes 'st' (abbreviation).
'raising money' becomes 'for cash' (as in doing something for cash).
'st'+'forcash'='stforcash'
'rapped' placed within 'stforcash' is 'STRAPPED FOR CASH'.
'to offer' acts as a link.
(Other definitions for strapped for cash that I've seen before include "Hard up" , "as an S & M prostitute?" , "very short of money?" , "needing money" , "not rolling in it" .)