This was my first experience traveling to Spain and my first experience using Airbnb so I was a bit apprehensive but our host made the process so easy!
Let's start with the location. This unit is centrally located about a 5 minute walk to Plaza Mayor and about a 10 minute walk to Puerta del Sol. There's the Diya market around the corner for essentials (don't forget to go upstairs for dry goods, toiletries, beer, etc.). And small restaurants, little shops and local color are everywhere. Madrid is a walking city and we walked between 15,000 and 20,000 steps every day.
The unit was as described and as photographed. The beds were very comfortable with crisp cotton sheets and pillowcases and plenty of good quality pillows (bad pillows are a pet peeve of our family). The kitchen was well-appointed and a care package of milk, cereal, treats and water was left for us as well as maps and a binder with all of the info we'd need for our stay and how to operate the appliances.
With the windows open you will hear street noise at night. There are earplugs available but I didn't need them. And I'm a very light sleeper.
The building and unit is very modern and because of that, their security measures are on point. We felt very secure and safe.
Finally, Carmen is a master of google translate so communication between us was clear.