There is a straightforward automatic system to recieve an entrance card for the room. Unfortunately, as we arrived, we realized our card is not working. We had to wait until a cleaner comes to open our door. After several communications, we didn't manage to fix this problem before checking out. Thankfully, there was another card in the room that we could use after but that was it.
Be aware: Pictures shown on the ad do not mean you will be getting the same room. As with other ads we were expecting to get the room in the picture, however we got a completely different and simpler room that could have affected our decision if we had known before making the reservation. The room was clean, even though it suffered from overall damages. Towels had big dark stains on them.
The area is very good a few minutes walk from the Retiro. Easily accessible by metro or bus.