We loved our stay! We didn't meet Anna, but she was extremely communicative, often responding to our messages within minutes. Her mother was very sweet, and promptly let us into the apartment and dropped us off in her car at the local subway stop on our way out.
The apartment was big and beautiful, and very quiet --- it may be the only (or one of very few) residential units in the building?
The location is great, about a 5-8 minute walk from the Charles Bridge.
We had a great stay, and would return!