Dear Ton,
It would be nice to come in a clean boat. As a guest, this is what I expect.
It would be nice to have updated pictures of the same boat on airbnb. As a guest, this is what I expect.
It would be nice to have a response when the guest needs to communicate with you. As a guest this is what I expect.
It would be nice if you would accept my earlier checkout and refund for the night not spent at the boat as per your own policy. As a guest, this is what I expect.
My expectations were too high?
Lowering your price will lower your guests' expectations.
That would at least be fair.
Best,
Nico