10/10 would recommend!
This was an excellent place to stay for our week in Lisbon. There was a slight hiccup at self check-in but when we called the number Luis provided, it was sorted within 30 seconds!
The view is great and worth the hills. If you're nervous about the hills up to the apartment, don't be. It is really well served by buses which you can get off at the top and walk down (our preferred mode of transport after particularly long days out and about). Or taxis are also incredibly affordable... in comparison to where I come from anyway.
The apartment itself had everything we needed for the week. Nice and spacious, and was easy to keep cool in the September heat.