All I can say : it is the best place. I would rate it 5 stars like a top of the class hotel. The room is comfy, fresh and clean sheets with good quality pillow and matress. I care about interior design and furniture, if you care about that this place is what you are looking for. Simply beautiful.
Location is good. Close to most tourist destinations. Close to Termini Station, walking distance. Coloseum, Fontana DiTrevi are within walking distance too. Also close to supermarket and many cafes.
Finally Valentina is a friendly host. She speaks good English and she shares Roma's best kept secret. Ask her for the best Pizza in Rome (if not in the world).