I cannot stress enough. The apartment is awesome, right at the center of Madrid. Close to everything and centrally located. A block away from Plaza Mayor, one of the places you must visit when in Madrid, close to a metro station where you can reach pretty much everything in Madrid. If you prefer to walk, pretty much 30 mins is the longest you will walk to reach one of the main attractions in Madrid. The apartment is so close to so many wonderful restaurants and also just about a block away from Mercado San Miguel!
The apartment is also very spacious, comfortable, well equipped. This was the best vacation I had in a long time.
I also had to work, and the wifi was very good and I was able to enjoy the city during the day and work at night no problem. If you are looking for a great place with a great host, this apartment is the one you must come to. I will certainly will want to return here.