The location of the house is very good. You can walk up to the museums. The main train station Atocha is very near.
Having said that, let me talk about the downside of the place.
First of all the address in the listing is faulty. It says Calle Salitre 4º 2, Madrid. The house no is actually 24. We were waiting outside the wrong house for a long time. But communication with the host was good and when we called him he immediately gave us the right directions.
The other problem was, there was nothing mentioned about checkout time on the website ( at least not in English) so we assumed that we could stay on the whole day since our flight was late at night. But the host said that there was another reservation at 1:30 PM. The host helpfully suggested that we could keep our luggage in the left luggage centre at the station. We had to change our plans accordingly.
The house is very small. It is actually a single room divided into two areas. There was a single AC which was very ineffective. The so called bed room was very hot and not possible to sleep in.
Since the apartment is on the top floor it becomes exceedingly hot during the day.
One of the dining chairs was broken.
In the bathroom the commode was not fixed properly and shook when you sat on it.
The shower curtains were missing rings and the rod was very unstable.
The sheets looked unwashed.
The little balcony outside was dirty and smelled bad.
The overall maintenance of the house needs to be improved.