Car list including promotional item (8)
I believe the answer is:
roadster
'car' is the definition.
(roadster is a kind of car)
'list including promotional item' is the wordplay.
'list' becomes 'roster' (a roster is a list or register).
'including' is an insertion indicator.
'promotional item' becomes 'ad' (advert).
'roster' going around 'ad' is 'ROADSTER'.
(Other definitions for roadster that I've seen before include "Small open-top car" , "Open-topped car" , "An open car without rear seats" , "Old car" , "Open two-seater car" .)