The keys pickup for us was at the airport left luggage counter. It was difficult to spot as it was outside the airport. Its across the road, next to parking. It was a long walk. We were carrying a lot of luggage and also had an infant so it was difficult for us.
Apartment was spacious and clean. Its in a community and felt very safe.
The apartment windows face the street not the courtyard. So there was a lot of noise two out of three nights we stayed there. Mostly it was coming from the cafe below the apartment. The toiletries provided by host were also limited.
Location was approximately 15min drive from all touristy spots in Madrid. By taxi it took 8-12euros. There are a few restaurants, bars and grocery stores close by.