Great house in a great area. Conveniently located near to shops and metro stations. Only issue was finding the place, as check-in instructions contradict the location on map.
I would suggest finding a place called "Sawa Musical Studio" before you arrive. Drop a pin on it so you can see it on your map even if you're offline and head there. The house is right in front of it. Also, when arriving at Nakanosakaue Station, take the exit for the main intersection, then just turn right when you come up the stairs and walk straight down that road. If you walk past a 7 Eleven, an Italian restaurant and a Lawsons, you're on the right road.