Overall, I enjoyed my 3-night stay. I had read some of the 'bad' reviews (the smell, the sofa-bed, the stairs, the small size of the apt, etc. ), but I was just happily surprised. The apartment itself is quite nice - the shower is great, the kitchenette really has everything one might need, the sofa-bed was quite comfortable, the radiator really nicely warmed up the place, the linnen was quite clean, etc.
When I arrived, the window was open to aerate the place, meaning it only had a very faint smell of mold. But so this did not prove the be a problem at all. And yes, as people have mentioned, the place is 3.5 flights of stairs up. And yes, the stairs are quaint, asymmetrical - but that's part of the charm!
The only thing that I'd like to point out, is that while I was there (in Jan 2023), there was some construction going on in an apartment 2 floors down. Meaning there was a LOT of noise from about 9am onwards. But none of that is Carole's 'fault'. I warmly recommend this place!