We had a great stay at Elsa's apartment. She was flexible with our check in and met us at the flat even though our flight was delayed by an hour. When we left she got in touch about a bag we had left behind so we were able to go back and get it before our flight.
The flat itself is lovely, very comfortable and great for a couple. It's located in the heart of Alfama which is a great area to wander around and is near some excellent bars, restaurants and shops. There is a bakery just down the road that is excellent for breakfast too. Most of Lisbon's central sights are easily walkable.
We'd happily stay here again.