Very cosy, stylish apartment. The place is small, but every space is used creatively. Perfect for a person travelling alone. As everyone has mentioned before me, the stairs are indeed very, very steep (more like ladders), which can be challenging if you are carrying more than a backpack. It is an old building - you will hear everything from the neighbouring apartments (TVs, bathrooms, doorbells, people talking on the phone) and from the lively streets of Mouraria, which really gives you an authentic feeling and is all the charm of this place.
Although the subway and the iconic tram 28 are right down the street, you may also walk to pretty much anywhere downtown since Graça, Alfama, Rossio place etc. are really close by.