I had a wonderful stay at Carlota's. As a solo female traveler, I felt very welcomed and safe in Carlota's spacious and light filled apartment. Even though check-in was scheduled for a couple of hours after I arrived in Lisbon, Carlota personally greeted me earlier in the day so that I could get settled. She showed me around the charming apartment which has everything you could need for a short stay - a supplied kitchen, bedroom, desk, living room, and bathroom - and then she gave me a list of great recommendations (restaurants, activities, day trips etc.). Highly recommend this place!
Bairro Alto is a happening neighborhood with plenty of bars, boutiques, restaurants, cafes, and Fado spots. It does get a bit noisy in the evenings, but nothing too bad. Also, the apartment is up 2 narrow flights of stairs. Wasn't a problem for me, but wanted to note for handicapped visitors or those traveling with a lot of heavy luggage.