Why a dichotomy I would have thought you would have to take the whole life cycle of a vehicle into account rather than its individual periods of ownership. What difference does it make whether (all other things being equal) you scrap say a 20 year old one owner car and scrapping a multi ownership 20 year old car?

22 Plus Four KIMI
12 Plus 4 Sport OZZY
08 Roadster FELIX
06 4/4 70th LOKI
77 4/4 SEAMUS
85 4/4 MOLLY