Me and my boyfriend stayed three nights at carlos apartment in july.
First of all we were impressed of the perfect location of the flat, its two minutes walking from the plaza and metrostation "Sol" which is the heart of spain!
In this area are many restaurants, bars and even clubs. In the evening not only tourists but also madrid people meet up to enjoy nightlife.
Most of the sights of madrid are more or less in walking distance, for example about 15 minutes to the prado museum. But if its too hot to walk the metrostation is close by (Sol).
The flat itself is more like a little studio. It is the one room with the couch (if you pull it out it becomes your bed) and the little kitchen in it, as well as a little separated bathroom. For a short stay its totally enough.
When we arrived we just gave a call and after 10 minutes Mario (?) came and gave us the keys, a map and further infos.
All in all we had a nice time in a perfect location, thank you carlos!