Please be aware that there is a bit of walking to do to the Roman ruins and the Renaissance squares (at least 20 minutes, rather fast paced, to Navona, for example), so I would
advise elderly couples to be cautious when choosing Trastevere as a base camp.
Trastevere is simply an amazing place to spend your Roman holidays.
Dozens of great restaurants, 20-30% cheaper than in the center + great service, lots of tourists but tasteful and pleasant, not the mixed mob you can find swarming along the monuments and shopping streets.
Super laid back, open until late night, lots of students, the streets around Rome As You Feel Apartments are a delight.
A special mention to Fish Market restaurant (10 minutes from the apartment, along the Tevere, towards Piazza Venezia) - great value for money, great service, simple yet hip, no reservations, very busy at dinner but totally worth the waiting.
The apartment - I liked the renovation very much, its style and functionality. It's on a quiet street 5 min from the restaurants, the only noise source are other tourists, living on the same street, and scooters parking around but nothing annoying.
The host was very nice and I also recommend the limo service they provide - only 50 Euro from Fiumicino, totally worth it when in groups of at least 3 but also for couples, because a train ticket is 15 Euro and it takes you only to Termini, from where you need to get a taxi anyway (it's going to be around 15-20 Euro) or a bus (no tube station in Trastevere).