They say they take less than an hour to respond but it's not true. They didn't respond for 24 hours to my request to get check-in information so I had to call them a few hours before arriving to know how to get the keys! Also the cleaning lady had been misinformed about my departure date. She entered the apartment while I was there...
That being said the apartment is great. Well located, quite modern, large and very well equipped... and it was not that expensive compared to the other options I had at the time.