Casa Cavour was an absolutely ideal location in Palermo. Giulia was wonderful, very helpful about finding things in Palermo, providing me with a map of the city and pointing out various locations that may be helpful. She even set out biscuits and made sure there was milk and cold water in the fridge! The building is very nice, and in the daytime there is a doorman. The apartment itself is exceptionally clean and has everything you might need during your stay. The apartment has wifi, but also there is a computer should you be traveling without a laptop. Also, the a/c is a real lifesaver if traveling there in the summer! (units in both the living room as well as the bedroom).
Casa Cavour is located right at the transition between the modern shopping district and the old city center of Palermo, making it very convenient for both purposes. Teatro Massimo is just steps away, and the Capo Market is only a short distance beyond that. The area is very nice, with a perpetual exchange of shoppers and diners. At no point during my time in Palermo did I feel less than secure while staying here.
All in all my stay at Casa Cavour was exceptional. The only potential drawback is that the windows overlook a square with many popular bars and restaurants with terraces, so at night you do get some of the noise from below. I found that with earplugs this became no problem.