Roughly dash with rental car (9)
I believe the answer is:
cabriolet
'car' is the definition.
(I've seen this before)
'roughly dash with rental' is the wordplay.
'roughly' becomes 'ca' (abbreviation for circa).
'dash' becomes 'brio' (both can mean excitement or energy).
'with rental' becomes 'let' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ca'+'brio'+'let'='CABRIOLET'
Can you help me to learn more?
(Other definitions for cabriolet that I've seen before include "vehicle" , "convertible" , "Car with a folding top -- trace boil (anag)" , "Soft-top car" , "Car - old horse-drawn carriage with a folding hood" .)