We had an excellent stay. The apartment is centrally located - a very short walk from the Triana. Very walkable to the key attractions of the Palace and the Cathedral, this was important to us. The apartment is compact, as expected for a European city. It was comfortable for our family of three. Do bring your own amenities for use in the bathroom as others have noted.
Although the apartment is in the 2nd floor, there is an elevator which made it easy to haul up our suitcases.
Joaquín and his team were extremely responsive and helpful. We were able charge our kindle in their office since we had forgotten our charger before our long flight back to the States. They also helped organize a cab for our return, allowed us to store their luggage in the office after checkout, which was super helpful.