The apartment is wonderfully located, just next to Plaza de España, it is clean and has AC.
We never met the host(s) and had to use Whats-app for communication instead of Airbnb, which was a bit suspicious - we were not sure if the host was a person or a company, who wrote the messages (host or employee), etc. We also had to send all our details and copies of IDs via a separate booking platform, and we are not sure how to pull this data from the host's database.
The renovation in the building made our last week very noisy and cut off the internet connection for a few days, the host also ordered furniture replacement while we were in the apartment. Prior to arrival, we had no idea that the renovation would be happening at the same time.
That being said, whoever contacted us via Whats-app was very nice and did their best to use English with us. The elevator was working, the furniture was comfortable, and the construction crew tried to be as considerate as they could. Our experience was overall positive and we would book the same place again if we were coming to Madrid.