Rocio, the host, was probably the best host we're encountered in all our years on airbnb: she was very attentive and caring, and really went an extra mile for us - we had a very late plane, and she welcomed us even with some food she had bought in supermarket! We've got all local info and best recommendations from her as well, and communication (via whatsapp) was very fast; there, she offered us help if anything happened, and we're sure we'd receive it if we needed.
The apartment was exactly as we expected: very central, quite small but efficient, with good A/C and double windows, successfully protecting us from the noise of the street - perfect for sleeping at night / resting in time of siesta.
Will definitely stay here next time in Madrid!