Great location with a beautiful view of the river. Close to a train/metro station and walkable distance to the heart of the city (15-20 min). Easy access from/to airport in public transport.
It is well equipped and is suitable for one person or a couple. It's under the roof, so the bathroom is pretty small and it's probably not the best place for a tall person.
I really like my stay in the apartment. The only negative aspect I think about : if you stay for a while and want to cook, the only close supermarket (5 min) is a small one with a limited choice of products.
The communication process and the arrival procedures were very efficient. It's actually rented by an agency who has several places in Lisbon.
I would definitely recommend this place.