Pros:
Great location - close proximity to Trevi, Spanish steps and other sites. Get your walking shoes, you can walk to pretty much everything from this place
Flexible checkin (Marta accommodated us leaving our bags in the apartment while we waited to be able to check in. She did ask us to check out somewhat early at 10am but this is fair overall I'd say. She was good and accommodating.
Quiet location (will address why this can also be a con) that is secluded from the bustling streets of Rome with a courtyard area that is private and very pretty.
Cons:
Cleanliness - everything there seems a bit outdated and there is an overall stench to the place that honestly makes this place tough to recommend. It is dusty, the sheets were gross with a similar stench to them as well
The Neighbors - I'm pretty sure these are oldschool Italians that want quiet and don't like dealing with tourists from other countries. We were whispering late at night in the courtyard and this somehow woke up an older lady that decided to scream at us from across her balcony. I genuinely don't think we were being loud, but maybe the fact that it's a closed-off courtyard amplifies the noise being made from inside. Maybe good for families that are looking to get to bed early - terrible for young 30-something professionals looking to enjoy some of the nightlife available in Rome.
The 100 degree elephant in the room - Air Conditioning. This might not apply during the time you are visiting but when we were, the weather was pretty hot. You don't have access or control to the air conditioning and the building seems to shut it off at 11pm and turn it back on at 9am. Now this might be okay if you were able to crack some windows, but there are no windows in Marta's apartment. Honestly unbearable to sleep there. We considered leaving midway through our stay but decided to persevere through it.
Bedding - terrible. The bed feels like you are sleeping on a wooden board in the main bedroom. It is so bad and my back still hurts from the nights I spent on it. Same with my friend. I had a friend that slept in another room. The springs were nearly poking through the mattress. The bedding needs an upgrade asap. Pillows are terrible as well and the sheets seemed dirty and definitely had a smell to them, almost like sweat or something. Just a terrible sleeping experience when coupled with the hot temperatures.
Overall: I cannot recommend this place to anybody. It is a good location and I can see how it might be more friendly towards a family but in good faith given the state of the place, I can't recommend it. It's kind-of gross and the entire apartment smells.