Hi,
there is is a free 48 h delay for cancellation whatever your policy. Means that Booking/cancel on the same day (even the day of arrival) means full refund (except for Airbnb fees)
(Link:
https://www.airbnb.fr/home/cancellation_policies#strict-with-grace-period )
Whats better (and it happened to me twice): when the guest cancels on the day of arrival (or even after, if he finally did not show up) , he can still write a review.
(Mine never did. If they had written a review, i would have called Airbnb to have these removed because thé guests never even travelled to my town).
Best,
Anne