There were many wonderful qualities about this flat. However, the water heater made a intermittent (but constant) high pitched howling noise that sounded like an abandoned dog. Our host sent technicians the day after it was reported (excellent response) but it was not fixed for our entire stay causing sleep disruption for those sleeping on the lower level.
I made a mistake on our reservation and we were granted another night which displaced the next guests. Very appreciative because it would have been horrible to find a place to stay for one night.
The next guests probably would have had to deal with the same howling nuisance (since they were due to arrive the next day) so my advice is for future guests to ensure this is fixed.
Otherwise this would have had a better rating. I guess a review question could be added such as “were all appliances in good working condition?”.