We loved our stay at Testaccio 45 and hope to return in the future. The apartment is bright, spacious, stylish, modern, and clean. It's exactly as depicted in the photos--a beautiful place. The apartment has a full (and well-stocked) kitchen, so you can cook meals yourself. The supermarket is only a block away. The metro/subway is about a 12 minute walk away; we generally rode the buses, which have very convenient stops nearby and take you to main sights (such as the Vatican and the Pantheon area) in about 10 minutes.
Sonia's sister-in-law met us outside the apartment building and got us settled in and oriented when we arrived. Thoughtfully, she also provided us breakfast for the next morning. Communication with Sonia was quick and easy; she's very responsive. I accidentally left €145 in the apartment when we left; Sonia let me know and we quickly worked out a solution to return the euro. She went above and beyond as a host. Highly recommend Testaccio 45 and hope to return. Thanks again!