The apartment location is great. Right next to a big park where you can run/walk in the morning or whenever you like. A ton of excellent restaurants in the vicinity. Public transportation is convenient: bus stop is right next to the building and the metro station is less than 10 minutes stroll. All major attractions are easily accessible by public transportation or if you are in the mood you can just walk through Retiro park to Prado or Thyssen museums. The main train station Atocha is 15 minutes away by bus in case you want to check out other towns while staying in Madrid.
Paz is a great host. Very friendly, quick to respond and always willing to help.