Professional agents, upwardly mobile, do well (7)
I believe the answer is:
prosper
'do well' is the definition.
(I've seen this before)
'professional agents upwardly mobile' is the wordplay.
'professional' becomes 'pro' (abbreviation).
'agents' becomes 'reps' (representatives).
'upwardly mobile' is a reversal indicator.
'reps' reversed gives 'sper'.
'pro'+'sper'='PROSPER'
(Other definitions for prosper that I've seen before include "Flourish, do well" , "like Merimee, nominally" , "Do well, be successful in life" , "Thrive, boom" , "Get rich" .)