Rosa was an amazing host. She greeted me with a large smile, showed me the apartment around, taking the time to explain how everything worked.
She also helped me with the "visit program", dividing the city in three distinct parts to visit and each time giving me some good addresses. She also told me a free, open-air concert was to be given in front of the Palacio real, making me having a wonderful night.
The apartment is absolutely beautiful. The only remark is the lack of luminosity in the kitchen part. However the bed is really comfortable and the room has large shelves and storage for clothes.
The apartment is perfectly located at the very foot of Gran Via metro station - the downside being that at night, the street is a bit loud. Absolutely everything is nearby (from supermarkets to restaurants, along with all touristic areas).
I would really recommend this flat!