Where to start...
Here in Latin America, when you talk about a hostel you think of a backpacker hostel, with shared bathrooms, shared rooms with bunk beds and - hopefully - lockers to store your luggage. That's not the case in Spain where a hostel is a small, family-owned hotel, without some of the facilities of large chain hotels (such as restaurant, elevator, parking).
The Ballesta is a comfortable and quiet hostel, located 1 minute walk from Gran Via, close to metro and bus stops, supermarkets, restaurants, bars and dozens of shops. The staff is very courteous and gives you recommendations for your walk through Madrid.
This hostel has an elevator. The room was clean and had enough for a short stay. They offered me a balcony overlooking a quiet street, which allows you to open the window if you dare against the cold winter nights in Madrid.
I returned the following week and I will return when I have to stay in Madrid on my way to other cities.