Amazing apartment, one of the best Airbnbs I've ever been in. Superb location too. A supermarket and Metro station within metres of the front door - and so central that you don't even need the Metro that much (I walked to most places that I needed to go to!)
Check in was smooth and straightforward, and they even messaged me during my stay to ask how it was going and if I needed anything (I didn't - everything was going great!)
Overall, an excellent apartment and I will definitely stay here again next time I'm in Madrid