Probably the best location in Madrid. Smack dab in the middle of everything you want to see and experience.
The flat is a simple 2 bedroom flat with almost no natural light and a concrete floor which will freeze your feet off.
However, since we were never home during our visit - there's so many things to experience - it really wasn't an issue. Everything else was great - it was clean and simple. This is obviously not a personal home and I highly suspect that 'Marina Y Juan' is a cover name for a small company with several holiday flats in Madrid.
The communication was quick, precise and friendly.
A great great great place to stay for an extended weekend in Madrid. I would definitely consider staying here again. Everything just works.