We stayed 6 nights at Christian's apartment and had a great time. He was extremely easy to reach and responsive to questions, and his English is excellent. The neighborhood was the perfect location for us, very walkable and 5 minutes to 2 different metro stations. The apartment was plenty of room for 2 people, and we enjoyed having access to a full kitchen and a washer/dryer. The heated towel rack in the bathroom was an extra treat!
The street that the apartment is located on is a quiet street, although even with the windows closed we could at times hear the street noise. It did not bother us however. There were shelves, but much of them are taken up by decorations, antiques, etc., rather than being available for guest use. Having 2 nightstands on either side of the bed would be also really helpful. Christian is an excellent host and we would highly recommend him.