The apartment is beautiful, large, clean and well furnished. As for location, it could not have been better! Yes the stairs are a slog but we were well warned about that and for myself (a fit 40) it was no bother at all.
There were a few snags during our stay that brought the experience down a bit. The hosts changed the door code a few hours before we arrived, and since I didn't have data roaming on my phone I didn't get the message. It was rather stressful after a long journey, in the cold and dark, to stand in a tiny doorway wondering why we couldn't get in. I get changing up the code, but to notify us of a change literally a few hours before check in when it wasn't guaranteed we would even get the message really sucked.
The heating and hot water was also broken on our first night, and it was damn cold so we had a sleepless night. The hosts were excellent about it the next day, super fast fix, but even then the front bedroom remained cold during our stay.