This flat really exceeded our expectations. Beautiful building with a shared courtyard, which we dined in one lunchtime. The building has a communally-owned cat named Lolo, who kept us company. Comfy bedroom, a very nice bathroom with an excellent shower, and a well-appointed kitchenette. Rodrigo was very helpful with check-in and booking, and provides a landline phone with his number on speed-dial, in case you need to contact him.
The neighbourhood of Lavapies is a bit rough - noticeable more so than other parts of Madrid we saw. There are some shifty characters on the streets at night, and you should keep your wits about you. That said, it's a wonderful neighbourhood during the day, and it has some great local joints, like La Mina, a proper local boozer that does vermouth and excellent, very cheap gambas a la plancha. It's also very central for Madrid's main sights, as well as for Atocha station.
Overall, we'd definitely consider booking this flat again. Thanks so much to Rodrigo for a wonderful stay!