I stayed at the Tiber Inn with my boyfriend for two nights, the experience was really bad from several points of view. The room is underground, and although it must have been recently renovated, it is so humid inside that the plaster is already coming off the walls. The air does not circulate, it is very dump and hot inside, and the walls are so thin that we could hear everything that was going on in the other room. If you happen to be there during school time, be prepared to be waken up early by a lot of noise, as the room door is in front of a high school. You can hear motorcycles and people as if they were by your side.
We asked for a double room, but they have none (though they did not tell us when we booked). When we arrived the two beds were next two each other with separate bed sheets. We did not even found towels in the bathroom, let alone soap or even toilet paper. We had to ask the staff for anything that one expects to find in a bed and breakfast.
When we asked the reception about these problems they minimized, promising to change our bed sheets into one for a double bed, but it never happened. They were quite aggressive when we complained about their service.