Excellent location apartment. Only 10-15 minutes walk away from Plaza Mayor, Puerta del Sol and La Latina district where all the cool bars and tapas places are at. The main train/bus station (Atocha) is also just 10 minutes walk away.
The apartment was super clean, located in an older building but it is completed renovated and modern inside the apartment.
Fernando was very helpful with tips and suggestions and we communicated on whatsapp and answered all our questions immediately.
Highly recommended, I will definitely stay with him again when I visit Madrid next time =)