If you're looking for something really nice - that's it. We arrived in Madrid late at evening and there was no problem for Mercedes to wait for us. At the day of our departure she was also very nice and allowed to leave our bags in room (no one was coming this day).
Room is not big but enough for 2 people. Blanket is so warm! We loved it. Every morning Mercedes gave us coffee, tea, toasts with jam. Bathroom is great - it was important for us to have enough hot water and it was no problem.
One thing to notice - there's no elevator in house but Mercedes also helped us with bags.
The place located in quite neighborhood near 2 metro stations of different lines. But if the weather is good you can walk to the city center (Royal palace) in 30 minutes. DIA supermarket is in 5 minutes.
It was our first airbnb experience and it was great. Thanks a lot, Mercedes! Спасибо!