It's a 10-minute walk from Roma Termini and tucked into a quiet area by the German, Russian, British, and Turkish embassies. Marked only by a modest label of "Booking House" by the buzzer, it's clean, small, and quite perfect.
Tatiana is quite possibly the most pleasant people I have met in my travels. She took the time to give us a map and show us the best routes to all the Roman destinations we had time for in our short stay, as well as outlining the best way to take the metro and how to get to the airport. Our room was perfect for two people. It was sunny and had a good atmosphere. The bathroom was clean and functional, and the water had good pressure. All-in-all, for the rates that we stayed and the reasonable distance (30 minutes on foot to the Colosseum), it is a place I'd explicitly recommend to any of my friends who find themselves in Rome one day.