My partner and I have just finished a 6 day stay in Valerio's apartment.
Valerio was great with communication! His sister was waiting at the door of the apartment complex when we arrived from our taxi ride from the airport.
The apartment was nice but small. Very small bathroom and the shower seemed to fill up with water very quickly (maybe poor drainage or blocked pipes?). You can not have a shower for longer than 5 minutes without the water overflowing. Other than that the apartment was great. It had a big bed, microwave/oven, stove top, kettle, fridge, washing machine, small clothes airer.
The location was AMAZING! Central Rome! Only a few minutes walk to the Flaminio train station. We were able to comfortably walk to the Pantheon, Trevi Fountain and Spanish Steps. According to Google Maps we could have walked to the Vatican and Colosseum within 30-40 minutes but we chose to catch the train as it was hot and the train system is quite cheap and easy to use.
The apartment was close to heaps of shops and restaurants - all within literally 5 minutes. You can choose to shop in the local shops or there is the bigger brands available as well - Prada, Liu Vuitton, Chanel etc.
I took stars off the price only because it was a little expensive when seeing the size and style of the apartment. Whilst it was a nice place. Although, I am not sure how pricing works in Rome. Maybe you pay more for the amazing location.
I would suggest this apartment to anyone who wants to be close to restaurants and shops in Rome (especially those who will not be hiring a car) and don't mind a bit of walking or are happy to catch the train in Rome.