We had the best time in Alice and Mike's apartment. Even though it's not situated right in the center, it doesn't matter as you are still within walking distance and there many options for public transport. There are buses that stop in front of the apartment but we mostly used the Santa Apolonia train/metro station that's a 5-10 minute walk away. The apartment itself was wonderful. Clean, well decorated, with good furniture and a well-equipped kitchen, and a little outside terrace. It can be slightly noisy from traffic in the the streets at night if you sleep with a window open, but it's nothing too extreme (I tend to a be a light sleeper so always bring earplugs anyway). There are also some Portugal/Lisbon guide books provided so you can get some inspiration on what to do or where to go if you don't know already. We met Alice and her kids on arrival, and Mike when we left, and they all were very friendly. Obviously, since they are American, communicating in English is easy :)