The flat is in the center close from all the places you must see in Prague. It is very quite, nothing will wake you up during the night.
Hana was a great host very communicative. We had a problem with the door, Hana was there in the 15 min to tell us it was fixed. She's let us maps and guide books. The appartement was clean.
The district is very nice : the old square with the astronomical clock. You can find good restaurants, bakeries and bars very close.
After 5 min walking you can visit the old jewish quarter.