What a fun way to experience staying in Amsterdam!
As noted, the space is not big. But with the windows open and the rooftop terrace, it really does feel comfortable. My wife and I had our one year old baby with us we definitely took up the maximum amount of room, but we were still able to stay comfortable. And all three of us loved seeing the boats and birds go by all day!
Valkira lives on the boat but with a private entrance you still have lots of privacy. I would definitely recommend staying here!