We loved our stay at Campo de Fiori. We traveled with a 20 month old toddler, who loved the apartment as well.
The location is exceptional for the walking tourist with a good pair of shoes. It is quite a ways from the Metro, but has several nearby bus stops, and is immediately near a taxi stand. The rooftop patio was amazing. We were able to enjoy it every afternoon during baby's nap and every evening when we often brought takeout to the roof and enjoyed the view with a bottle of wine. The kitchenette was appropriately stocked, the apartment very clean.
I would highly recommend booking a transfer from airport directly from Andrea as it is the going rate and it would help alleviate a minor headache getting there and checked in.
Our stay and host were great, and this spot was perfect for our family of 3, we were very grateful for the long pack-and-play for the baby, and the fact that we walked out directly to the Campo De Fiori with it's own market and evening festivities, only 2 blocks from Piazza Navona.