Man determined to secure right type of vehicle (7)
I believe the answer is:
servant
'man' is the definition.
(thesaurus)
'determined to secure right type of vehicle' is the wordplay.
'determined' becomes 'set' ('set' can be a synonym of 'determined').
'to secure' is an insertion indicator.
'right' becomes 'r' (common abbreviation).
'type of vehicle' becomes 'van' (**).
'r'+'van'='rvan'
'set' enclosing 'rvan' is 'SERVANT'.
(Other definitions for servant that I've seen before include "Personal attendant" , "Worker in household" , "Menial" , "Perhaps help" , "House employee" .)