Excellent value for money. First of all, the hosts makes it easy for you to check in whenever you can. She is super responsive and communicates closely, if you need her help.
The location is just super convenient. It’s in el Centro, so you can walk to Retiro, Museo Prado, place Mayor, Real Palacio, Cibeles, Gran Villa and the Atocha massive train station to get the metro or train to Madrid Airport. Behind the apartment is a Carrefour supermarket, within 2 blocks you will find many decent small restaurants and your usual US-chains such as Starbucks.
I personally liked being near Av Castellana as you can go to many major places in Madrid readily by metro or Uber/taxi, ie the Estadio Bernabeu, government offices, 4 Torres, and Hospital La Paz and Ramon y Cajal.
The apartment itself is very comfortable. It can easily accommodate 4 adults. Beds are comfortable. The WiFi is super fast at 100 Mbps download speed, TV is Amazon Fire. You have a washer and a rack dryer! It was super convenient. Shower water pressure is good too. The noise insulation is good so you can easily sleep and not hear much street noise and never the neighbors from the bedrooms.
Make this your priority Airbnb rental if you want a place in el centro, which I would recommend for anyone that doesn’t already need to be specifically based in one particular location during your travels