Certain car deal (5)
I believe the answer is:
lease
'certain car deal' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for lease that I've seen before include "Rent (a property)" , "Rent -- easel (anag)" , "Contract to rent" , "Contract for, say, use of building" , "Let; rent" .)