Fantastic location! Bang in front of Mercado de San Miguel, where you can watch the food stalls prep delicious tapas from your window. The area is splattered with restaurants, cafes, bakeries and souvenir shops. And there is a street close by that has the highest concentration of restaurants per square meter in the world.
Sol, Opera, Palacio Real, Gran Via, Playa Mayor are all within a few hundred meters. The hop-on-hop-off bus route-1 (historical route) stops barely a hundred meters away and tuk tuks wait outside the San Miguel market to take you on sightseeing trips around the city. This, in short, is the beating heart of the city.
The apartment is very clean, well appointed and has been recently refurbished. There are two spacious bedrooms with comfortable beds and a living room with a four-seat dining table. There's a spacious and modern bathroom and a small toilet to cover for emergencies. The kitchen is small but has induction cooktop, microwave and dishwasher. There isn't too much backup supplies except the basics, but with food all around, you may not use the kitchen much. The apartment is on the second flour, and has an elevator that fits 2 people.
If you wan't to stay in a central location from where you can walk to many of the touristic and commercial areas of Madrid, then this apartment is your best choice. It's spacious and good for a family of four people, and despite being so close to the market is surprisingly quiet at night. I highly recommend this place.