We had an extremely perfect staying at Diego's place in Malasaña. The apartment is amazing, very authentic with a great design and many interesting details. Everything is brand new and we could even had a working meeting with some colleagues in the cozy basement which is gorgeous to work in.
Diego is the perfect host, extremely friendly, helpful and such a nice guy.
I highly recomend this fantastic place if your planing to visit Madrid. You wont regret!