Tana has been very quick to response to messages and helpful when we needed her.

Location: 5-star for a few reasons: it is in a quiet area in the Jewish quarter. You are close to the tram and metro, and within walking distance to many sights but away from noisy tourist-packed areas. The bedrooms are on the street but it is very quiet. There are some good restaurants in the area. Try Lehka Hlava (not exactly in the area but within walking distance).
Space: The apartment was adequate for 4 people if you do not mind sharing beds. A 5th person can sleep on a bed on an elevated area but there is not much head space there. The place is great for 2 couples.
Facilities: Good wifi, and coffee percolator came in handy. Cooker and washing machine were available but we didn't use them. No soap on sink and no washing liquid for the washing machine but wasn't a big issue for us.
Cleanliness: The apartment was spotless and amongst the cleanest I've been to.