Model runs into busy places - does well (7)
I believe the answer is:
thrives
'does well' is the definition.
(I've seen this before)
'model runs into busy places' is the wordplay.
'model' becomes 't' (Ford Model T car).
'runs' becomes 'r' (cricket abbreviation).
'into' means one lot of letters goes inside another.
'busy places' becomes 'hives' (I've seen this in another clue).
'r' put within 'hives' is 'hrives'.
't'+'hrives'='THRIVES'
(Other definitions for thrives that I've seen before include "Flourishes, prospers" , "Prospers, does well" , "Is very healthy and does well" , "Develops well" .)