Exceptionally good location, close to a lot of lovely restaurants and bars, taxi stands, motorbike rental stores, etc.
We visited in mid-July and did not expect the place to be as hot as it was (probably the worst time to visit Madrid!) and the apartment did not have any air conditioning or fans (in the bedrooms). The only fans were in the living room and kitchen/ dining room. We had an uncomfortable first night and bought 2 table/ standing fans for the 2 bedrooms on day 2. The host kindly refunded us (and some) for the same, which we truly appreciate.
The house itself is lovely - it had book shelves filled with books all over the place, the kitchen/ dining areas is spacious (as are the bathrooms) and the living and bed rooms are pretty big too.
Overall a great experience but for the first night without any fans. New guests won't have that problem any more :)