Pilar is the best and the apartment couldn't be cuter!
My wife and me stayed for a week and we loved the apartment, it is a newly renovated apt within a traditional old building on one of the most happening neighborhoods in Madrid which is Malasaña. The place is neat, clean, well equipped, quiet and super well located.
Pilar is very helpful and communicative, I'd highly recommend it for a couple or a single person.