Being a tourist/traveler (however you want to flip it), it's hard to know the lay of the land without ever being there. No amount of guides or reading will let you know where to stay for the best time.
I am happy to say that this place is the perfect location in Madrid.
Reyes's place is situated in the heart of La Latina, where some of the best tapas bars are situated. Tired of bar hopping? The famous Mercado San Miguel is a short walk away. Drunk walking after bar hopping? San Gines's churros is another short walk away.
Book this place.
Besides the location, the listing/apartment was clean and thoughtful. Very modern and perfect for two. Any more, you will be on top of each other.