Our stay was overall very nice. The apartment/room has everything necessary for a couple on a short holiday, including a fully stocked tiny kitchen and a reasonably-sized bathroom. The location couldn't be better, as it is a 5 minute walk away from La Giralda. It is surrounded by narrow and quiet streets, but within a few minutes you get to the restaurants and shops.
However, the main fault of the apartment is the cleanliness. The furniture had a thin layer of dust, the floor hadn't been swept, there was some hair in the shower, and the sheets were lightly stained.
It should also be mentioned that the room has very little natural light and that the walls are paper thin, so you hear every noise in the street. The room is in an old building, so there's a faint smell of humidity, but that didn't really bother us once we got used to it.
That being said, we spent most of our time outside, so the apartment's central location proved to be very useful. Blanca and her family were helpful and very flexible with our schedule, and we had a great stay.