Monica & Bruno's apartment is a right at the centre of everything! Not only that, her home is tastefully decorated! It has all the amenities that you require. We stayed for 5 days and it really felt home away from home. Most importantly, Monica is a great host who personally takes care of your stay! Would love to come back!
Tip: Considering Lisbon is a hilly city, get down at Martin Moniz or Baixa-Chiado station (instead of Rossio) if you have a lot of luggage (like we had). You'll have to climb fewer stairs to reach her apartment. Otherwise, Rossio is the nearest!