We stayed in the Principe Real apartment one night and we had spent three nights before in the Orange Tree apartment: both places are very comfortable with a very tasteful interior. The information provided before was clear and very helpful. The Principe Real apartment has a great location as you can literally walk to all the nice neighbourhoods of Lisbon. The Orange Tree one is a bit further out, but that was great as we had a car and parking is free, plus access with metro to town is quick and easy. I would definitely stay at their places again!