We stayed for 5 nights, the room was perfect, the bathroom is ok if you are careful to not wet the floor while showering (Freddie cleaned the bathroom after us a couple of times); we ended up not using the kitchen. It is possible to smoke inside.
Position is very good, there is a coffeshop downstairs, near supermarkets and it is 5 minutes from the central station (while it takes 30 minutes to reach Vondelpark and the museums).
Maybe it is not the cleanest room in Amsterdam, but Freddie is a kind person, he provided us with everything we needed and he was available.
We would book the room again if visiting Amsterdam another time.
His cat is amazing.