What a lovely apartment! The full height windows facing the river provide a great view and plenty of natural light. Special touches include a bottle of local wine and a very well stocked kitchen, including decaf coffee to the delight of my partner. We loved the location in the Alfama, and walked everywhere. The few times we used other transportation, we walked about 2 minutes to the square near the Fado museum, and grabbed (an incredibly cheap!) Uber. The host provides a very useful notebook with suggestions of restaurants and activities.
The apartment has enough beds to comfortably sleep 4 or 5, but would feel tight for that many persons otherwise. We found it perfect as a couple because we used the second bedroom with bunk beds as a closet /dressing room. The bath and kitchen are a one-person-at-a-time only size.
The bedroom has a ceiling fan, and a transom light (rather than a window). Street noise, and movement outside the apartment door, is readily heard inside the apartment. I didn't find it to be a problem, and in fact loved the sounds from nearby Fado performers wafting into the open windows. (I find it's always a good idea to be equipped with earplugs and mask.) The mattress was much firmer than I prefer, but it was not the dreaded bare springs or concrete slab found in way too many airbnbs. If I visited again, I'd request the host provide a top sheet so that I'd have better control over sleeping temperature, rather than the all or nothing duvet-only set up. Our visit was at the end of September, so the temperature in the apartment was very comfortable.
If you aren't physically able to negotiate hills and stairs, then better to find a drive-up hotel with elevators in another part of the city. But if you want an authentic experience in the thick of the historic Alfama, then you could not do better!