From the day we booked, Federico was in touch by email. Easy to arrange our handover of keys. We flew to Fiumicino airport [the closest to the apartment]. The official, white taxis charge a flat rate of 48 euros [avoid the taxi touts on the way to the official taxi rank - they are likely to charge even more and they may not be insured in case of accident]. The journey was under 30 minutes with clear traffic and felt very overpriced. A better option would have been to take a train to Ostiense and then either a white taxi from there or the 769 bus, which will eventually drop you immediately outside the apartment block as it comes back down the one way street - Accamemi Agiata [Augoustina stop]. You'll just have to check the precise route.
The nearest metro is Saint Paolo Basilica - this takes you straight into the centre on the 'B' line. We found that using the 1.50 euro combined ticket [bought at the station ticket machine, or at tobacconists, etc] was useful. They give 100 minutes journey time for unlimited bus use and for a single metro journey. Just make sure at some stations [for example Circo Massimo] that you enter the correct entrance for the direction of travel, otherwise you will have to buy another ticket!].
The S. Paolo Basilica station also has a direct line to the wonderful preserved ruins at Ostia Attica [25km away/25 minutes] using the same combined ticket for 1.50 euros. Excellent value and a terrific day out. The entrance is 8 euros [full] with concessions for EU teachers [4 euros with proof shown] and free for journalists!
A walk upto the Garabaldi moment in the Gianicolo area gives a lovely view over the city and, on the way up, the Fontana deli Acqua Paola is a rival for the Trevi fountain and has a great view of the city in addition.