@Barry-and-Lera0, the fear was, that people block a space with à down payment without any hope of coming up with the rest. If they don't win the lottery, they cancel and the down payment is refundable. In the French system, the first part was not refundable. In 10 years, we suffered one such cancellations, with a first payment of less ten 10 percent of the rent. In that case, the guest just did not show and we could not rent the week. Setting the non-refundable part to 30%, the legal limit here, it never happened again.
In the airbnb system, everything is refundable 30 days before arrival and that can really be a risk. If you see two or three flats, you like, you could block all of them till the rest of the family has made up their mind.
The other hosts may not be able to rebook.
I'd like to have payment in installments for longer stays, but with a fix amount, that has to
be paid even if the stay is cancelled.
As a guest, what would you believe to be fair? At which point would you only book, if you are sure, and only one place?