This is an apartment in the lovely area of Barrios Letras - super close to the museums, a walking distance to Puerta Del Sol, Plaza Mayor and Gran Vía. The apartment is not big, but is well planned - two full bedrooms with a shower and bathroom each - very convenient for friends or families. There is also a living room and a full kitchen, including a washing machine.
There is an elevator in the building, though there are three steps to get to it, please take that into account. The area does get a bit noisy at night, as this is where all the bars are, but the windows are good and the bedrooms only have an internal window, so close the door and hardly any noise at all.
I had to pick the keys up at a lockers store nearby, but received very detailed instructions so that was easy.
I would suggest adding some anti-slip stickers in the showers, as they were a bit slippery. Otherwise - I would definitely recommend this apartment!