I stayed in this apartment for a week. It looked just like the pictures, was comfortable and clean. Miguel was easy to communicate with via the Airbnb app. For my check-in he was unavailable to meet me personally, but left the key at a nearby cafe. That was a very easy process.
As others have noted, the apartment is on the top floor of a 4 story walk-up. The ceilings are low in some places, so just be aware of that. (I'm tall, so I just had to watch my head.) Despite being near several bars and restaurants, I found the apartment and the neighborhood pretty quiet at night -- though it's worth noting that on the weekends Lisbon is a stay-up-late city, so you may catch some noise on Friday or Saturday night just because it's part of the culture.
Overall I had a great stay and would recommend this place to others!