We enjoyed our stay at Marco's very funky flat.
It's not big, but comfortable when you are there for a few days.
The stairs up to the flat are quite steep and long, so it's not well suited for people with leg problems or poor fitness.
For us it was a helping hand to burn off all the pasta and tiramisu that you unavoidably will consume in that city ;)
The location is very good! The neighborhood feels very safe and comfortable...but lively nightlife is just 6 minutes walk away.
We rented a Vespa from OnRoad rentals...which is also 6 minutes walk from the flat. It's a fun way to be in Rome...and highly recommended.
Marco arranged a taxi pickup at the airport, and one from the flat to the airport ...it's 50€ pr. trip, and was very comfortable and worth it.
Overall we highly recommend this apartment and Marco's service.