My biggest selling point was that my flight got in at 8 in the morning, but all the Airbnb check ins were in the afternoon. This was the only place that had luggage drop off and it was so clutch. Scarlat met us in person and stored our luggage in his own unit until we were ready to check in.
Additionally, the apartment has amazing sounds proofing and black out curtains. It is in a very central location with a busy street, but you can't tell once all the window treatments are used. Make sure to shut all the window treatments for a deep sleep.
To top it all off, Scarlat let us know we could have stored our luggage with him in the afternoon of our check out date. He is the best and it made our first day in Madrid a success where it could have been a nightmare.