What a fabulous place to stay. Really central to the Nobel Museum and the palace and a pleasant walking distance from the central station. Close to lots of bars and restaurants. The apartment itself was just like the photos - really quirky and interesting with plenty of room and all amenities. The church bells do ring every 15 minutes, including through the night, but you can't really hear them in the upstairs bedroom - although I suggest ear plugs if you sleep in the main bedroom.
Having two bathrooms is very handy and there is plenty of room in the apartment to spread out. Unfortunately we did not meet Helena, but access to the apartment was easy and obvious, and Helena's communication was excellent.
I highly recommend Helena's place.