Stayed at Tania and Philip's house last week...although they were not there when we visited SF, Tania communicated with us promptly and made sure I was in contact with their friend who hosted us. Like everyone has already mentioned, their house is beautiful, clean, and in a great location. Their friend was very helpful and approachable...suggesting places to eat nearby and places to go in the neighborhood. Would recommend staying with them if you want to stay in the city!