Margarida's listing had all that one can expect from a top host: thoughtful arrangement, clean, useful appliances, and all the essentials for one's stay. I don't need bells and whistles (though the views of Lisbon and the river are amazing,) but I greatly appreciate good soundproof windows like the ones this place has.
I stayed with my wife and my daughter, and we had a great time. The location is superb, enough to get the Alfama vibe, but only a block away from Baixa. You'll get your daily workout going up and down those streets (and the building; no elevator here).
We would love to book it again when we're back.