We loved our stay in Elena's apartment. The neighborhood feels quieter and homier than the more touristy areas of Rome, so the apartment was a wonderful place to unwind after a long day of seeing the sites. After our stay, we joined up with a tour we had booked and moved to a hotel - looking back, I think we would have preferred staying in Elena's apartment!
Elena was incredibly communicative during the time leading up to our visit, and generously offered some flexibility with our check-in process on the day we arrived. Elena's mom helped get us settled in when we arrived, and was very helpful. The tips Elena provided for local and city-wide sites and restaurants were excellent (we especially enjoyed Pigneto, and would have eaten there every night had we discovered it earlier).
If (when) we return to Rome, this is how we hope to do it again!