About 5 years ago we stayed at Hotel Nerva because we wanted to stay in that area. I made reservations about 6 0r 7 months out, as far out as I was allowed. When we checked in we were given directions to a separate building a block out and behind the hotel. Key for the building door and key for the room.
It was clean and bed was comfy, BUT the ceiling above the bed was low (and I'm short). The bathroom was tiny even by Italian standards. We had to leave in the morning, go around the block and turn in the keys. We had breakfast at the main building. The owner and his wife were nice and helpful. She made a great cappuccino but then in the evening we had to go pick up the keys and do the same thing.
My husband would not stay there again. Since I had made the reservations so far out, I was disappointed that I was never told that we were going to be that far away. No way to go downstairs and ask a question or for help.
Have a Great Trip!