I stayed at Isabel's beautiful place for one week and loved the location and the coziness of the apartment. I also liked that there was a heater which was very helpful, since many apartments don't have heating in Lisbon. You don't need a car, everything is walkable in Lisbon and Uber or public transport are fairly cheap. The only thing that was a bit annoying (but really nobody's fault) are the thin walls and ceilings. I'm fortunate to sleep very well and always travel with noise cancelling headphones but if you're a light sleeper this could be a problem. I heard everything from my neighbors above and next to me. Just something to consider.