Kate's place is an absolutely beautiful apartment that's very spacious for a studio, with lots of lovely touches (there's a coffee maker, a piano, and she left waffles as a snack) and it's in a perfect location in Amsterdam, central to a lot of site-seeing and attractions. The bathroom is great and it was spotlessly clean. The room is on the 4th floor so there are quite a few steps up to the room, but obviously that's to be expected for Europe.
The check-in process did involve making arrangements for a fellow traveler to pick up the keys for me during the day (which luckily I was able to set up while I was traveling in Belgium- Kate was very responsive and helped me figure that out) and then when I got in (unfortunately very late) on my first night, I discovered the instructions on which keys and doors to use weren't clear (plus I was super ill from dehydration) and I was very confused on how to get to the apartment.
But apart from those issues on the first night, which we resolved, I had a great time staying at Kate's place, and it's a really lovely spot.