Check in was an absolute nightmare. We had to download an app. We’re foreign and didn’t have cellular service outside our home country. We had to go to a cafe and purchase something to use Wifi to download the app. Half the time the app crashed. It took us 3 hours to download it and check in. Also, the folks running the agency responsible for this listing gave us the option to check in at their office but provided us the wrong address. They claimed there is only one Calle San Marco in Madrid. There are at least two. We arrived at a private residence 30 min away