The rule of the house is to treat everything with respect, and it was a pleasure to do so because everything is new, clean, and works properly - in the kitchen, in the bathroom, in the toilet. Hot water in the shower may cool down for a moment - nothing to worry about, it fixes itself in about 20 seconds. The water filled mattress was my first time experience with this kind of a bed, and I am definitely not getting me one of those ;) but some people might actually enjoy it better than a regular mattress. Thomas, the host, is very friendly and reasonable. The location of the apartment is fine - it takes only about 21 minutes of walking and riding the U3 to get from the door to the very center of the city, the Stephansplatz. I do recommend Thomas' place for staying in Vienna for a few days.