I LOVE THIS PLACE! Its hard to find anything better in Madrid - the location is incredible, the flat is pretty big, and the price is perfect.
I stayed here for a month and would absolutely recommend this to anybody for short or long term stays.
CHECK IN: I met Francisco in person to check in, he gave me a quick tour of the flat, explained which keys go to which doors, and then took off (I had just arrived from a long flight so I was dying to sleep).
LOCATION: You walk out the front door and you're able to walk to anything you need - grocery stores, restaurants, bars, nightlife. You can even walk to most of the major sights in the city, but the metro is so close that you don't have to.