Try looking at Booking.com as well. We recently had great luck finding well-priced B&Bs and serviced apartments with them throughout central Italy, including Rome. Their listings do include some hotels as well, and you can filter as appropriate. The ratings scores (quality and location) turned out to be very good and comparable indicators of what we were going to get, plus the map and pictures were invaluable. Just make sure to look at the pictures for the specific rooms you are interested in by clicking on the room type, as the general site listing includes all pictures for that property. Also make sure to indicate the correct # of people, as the places we stayed at did not typically have available rollaways.