I had an amazing stay in Palermo!
The terrace was beautiful, and I enjoyed it every day during my stay (Feb-April). The A/C works well (it sounds like previous guests had issues because the whole city had rolling blackouts on particularly hot weekends — not ideal, but not specific to the apartment).
Clara, my host, made a huge difference in my stay. If any issues arose she was very responsive and effective at resolving them. A small example was the toilet malfunctioning. She had someone there promptly, and it was solved within hours.
The location is wonderful for exploring the city at a relaxed pace. Lots of restaurants, shops, grocery stores, cafes, etc. It is a bit noisy, and I wore earplugs to sleep until I grew accustomed to it, but I do think if you want to be in a location where things are happening, you should expect to hear the sounds of things happening.
The wifi was fast and reliable. The desk is a great spot to get work done.
It's a place I would happily stay again. When friends staying at other Airbnbs came over, they were jealous 😬