The studio suffers from serious humidity and mold issues. It is apparently a common problem in all apartments located on the ground floor of buildings constructed of lava stone. Manlio takes good care of the studio and replasters the walls frequently, but this does not fix the problem - it only hides it. I spent two months there, in February and March, and it was like living in a cold and humid cave with mold spreading a little bit more every day. I cannot really blame Manlio because 1) the apartment was replastered before my arrival, so that it was just fine when I got the keys (but mold appeared in the bath room after only two days...), 2) I did not call him to complain (I did not see the point of doing so given that it is a serious, structural problem that cannot be fixed in a flash... He would certainly have let me leave and reimbursed for the remaining days, but I was in Catania for work and could not afford wasting time to find another lodging solution).
All in all, I do not recommend renting the studio for a long period of time and/or in the Winter, especially in case of allergy to mold or breathing conditions. In the Summer and for short, 2 or 3-day stays, the studio would be just ok.