We had lovely 4 days in Lisbon and enjoyed the apartment and its neighborhood a lot. The location is really nice - in the midst of the old district Alfama, where the streets are narrow, the people friendly, and the portuguese restaurants and bars authentic. The apartment is small, but has everything you could wish for, even a small kitchen. The windows aren't too bad. We were there during the month-long festival of Santa Antonio, but could sleep very well, even though there was a lot going on outside.
The only negative point was the communication with Ana, who lives close by and does the check in/out. My advice for you: don't communicate with her over text messages, as those are quite complicated - just call her! ;)