Perfect apartment for a couple. Apartment is on 4th floor (top floor), but has a small lift if needed. We just walked the stairs each time. The washer/dryer combo was a big plus. We visited during a record heat wave (about 40C/103F), and the A/C struggled a bit being on the top floor. Apartment was extremely clean and quiet.
Food markets, pharmacy and tapas bars are also very close. It was about a 15 min walk to Plaza Mayor. Apartment is very close to metro station Anton Martin.
Taxi from airport is a flat rate of 30 Euro. It was a bit cheaper with the Cabify App. We opted to taxi out to the apartment, and then taxi back to the airport to pick up a rental car for the remainder of our trip since driving/parking in the city is both difficult and pricey.