I booked this apartment for my boyfriend and I for 3 nights because of its proximity and how lovely it looked. It completely exceeded every expectation. Frank met us in the lobby of the apartment, which is only a short walk from termini and easy to find and showed us to the apartment. Frank then gave us a really comprehensive insiders guide to the city, pulling out places that we should see and giving us tips about the best places to buy tickets and travel. My boyfriend and I love trying new foods and wines, so Frank suggested his favourite places to eat and drink in Rome, all of which were amazing (if you do come and stay, make sure he gives you the address of the fish restaurant).
The apartment itself was really cosy and perfect for what we needed. The bed was really comfy, everything was very clean and the shower and bathroom were nice. We didn't cook, but it looked as though Frank's place had everything you could need to make a meal. Also has wifi!
The apartment was in a safe enough area, and had multiple locks and a lift to help you get to there (though it's on the first floor so you don't need it!).
The location was the main pull - colosseum and forum are only a ten minute walk and it's right next to the metro so great for getting to Vatican. It's also right next to termini if you're looking to do some wineries on your trip, you can easily get to places outside the city.
I couldn't recommend Frank and his apartment highly enough - we'll be recommending to our friends and family and if we do come back to Rome, we will definitely stay here again.