The location is perfect and the apartment looks unique, but consider these:
Even on a sunny day, the apartment is a lot darker than what is shown in the photos. There is also a strange smell of mildew and the bathroom ceiling has mold in it. I have stayed at several older building in Rome and haven’t had the same issues. Also, the unit is managed by several people and not all of them are equally communicative (some took 3-4 days to respond to questions, if a all). Also, we didn’t have internet on our last day, but it wasn’t an issue for us because we had internet on our phones.