I had a wonderful stay at Alberto's apartment. Firstly, the location is amazing! Centrally-located on Calle Mayor, across the street from the Mercado de San Miguel (a marketplace where you can try out all sorts of Spanish cuisine), steps away from Plaza Mayor, and a 5-minute walk to Puerta del Sol. All the shops, restaurants and bars you could ever hope for is easily accessible.
The apartment is located on the 8th floor, you can take the elevator to the 7th floor and the stairs up to the 8th. The rooms are exactly as shown, very clean and well-kept. The shower is tiny, but hot water is plentiful. Remember to bring your own amenities, you'll need them. Otherwise, you can buy them downstairs at the supermarket next door. A/C works like a charm, comfortable bed, TV reception is good. Alberto is extremely accommodating and responsive, a really nice host. I would recommend this apartment to anyone, be it for leisure or business, and would love to come back!
P.S. The doorman is super friendly and helpful, too!