Link here. Also in this report it says it was tape strong enough to hold carpets down that he bought on 28th Feb (not plastic carpet protector for wrapping seats).
“Detectives now believe Everard was transferred from the Astra to Couzens’ own car, somewhere by the Kent coast.”
How a white Vauxhall Astra led police to Sarah Everard’s killer
So if she was transferred to his own car he didn’t leave her at Hoads Wood- she was still in the Astra - either dead or alive. And he transferred her to his own car that night possibly on his way home (the car hire place is on the Kent coast - assuming he left his own car there)., So got home in the Astra without her in it. Took the Astra back next morning and picked up his own car with her already in it. Then - maybe to Hoads wood? Or elsewhere first.