Highly recommend staying with Conrado! I found him to be a fun-loving guy after we went out for tacos on our first night, when I arrived at 1am - which he had no problem with. The room is very centrally located, very reasonably-priced, clean with a good shower, kitchen and living room all available. The only thing to be aware of is that the bedroom does not itself lock, and the apartment is often shared with other people - all of whom I found to be fun, interesting people - but if you were bringing valuables, perhaps this would be something you could speak to Conrado about, in terms of securing your possessions. Overall, would highly recommend staying with Conrado, and would do so again should I return to Madrid!