First of all - I know nothing about rooms and accomodation at Residenza Belli. Rooms may be nice and well worth money - we never got to stay there.
I had booked 2 rooms for 4 nights. When we turned up the taxi driver had a hard time finding the property, and when we rang the bell no one opened. In the heat we started to ring other door bells, and in the end someone in another flat in the building opened the front doors for us. But we only came in to the hallway, and no one answered the bell here. After almost one hour the owner turned up, just to tell us he had some problems and there were no rooms for us. He had sendt me an e-mail - but I had been holydaying in Italy for almost two weeks, and only checked my e-mail now and then. He had rebooked us into a hostel close to Termini, but we had booked this place because we wanted to stay in Trastevere.

The owner drove us himself to the other property, and I think he was trying to do the best for us. We did not like this other place and only stayed there for one night, but that's another story.

Main complaines are that the property is hard to find, and that no one answered the bell when we tried to get in. I have read at Venere others complaining about the same.