Hey @Dan12468 ,
As already said, in the Strict cancellation policy it is stated that the guest cancelling any time up to 7 days prior to check-in can get a refund of 50% of the nightly rate - or 50% of the total amount.
So, if the total price of the stay is 100 €, they are eligible to a 50 € refund, the other 50 € stays with the host.
It does not matter if the guest paid only 50 €, that 50 € stays with the host, and you can regard the 50 € that the guest didn't yet pay as the refund.
Nowhere is stated that the guest gets 50 % refund of the amount they paid. Imagine that the guest would pay only 20 € at first for a 500 € stay, and then they would expect the 50% refund of the amount they paid... That would not be fair to the host at all.
So, for your previous question, if the guest paid 60 € out of 100 € and cancelled more than 7 days before check-in on a Strict policy, where the 48h grace period of 100% refund has already passed, the guest would only be refunded 10 €, as 50 € (50% of 100 €) will stay with the guest.
That is fair to both the host and the guest. Not reading the details of the cancellation policy and agreeing to them anyway is not an excuse that you should be getting a refund how you feel you should. If the guest wanted a full refund, it would be better to book a listing with Flexible or Moderate cancellation policy (and of course, read the policy carefully before agreeing to anything).
However, the guest always has an option to message the host and ask for the full/partial refund - though it is completely host's decision if they will give the refund or not. I know many hosts give a refund if the cancelled dates get rebooked, and I think that is a right thing to do too.
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Otherwise, terms of the cancellation policies are stated everywhere:
● The cancellation policies for the listing are written twice on the listing front page, at the top under the listing name...
Cancellation under the name
... and at the bottom below the reviews and house rules (where you can get more information by clicking Get full details).
Cancellation at the bottom
● Before securing the booking, Airbnb shows you (again) the cancellation policy for the listing.
Cancellation policy before finalizing the booking
... By clicking on "More details" there, it shows you the visual schematic even.
The visual cancellation policy
● And in the help centre, if you go there, you get all the cancellation policies visually shown for easier understanding:
● Flexible: Flexible
● Moderate: Moderate
●Strict: Strict
For more info on cancellation policies see https://www.airbnb.co.uk/home/cancellation_policies