This apartment is quite good! It is right next to Plaza Serrano, a main square in Palermo with lots of restaurants and bars. And even though it is very close to the bars, I didn't hear them at night. The apartment is very clean, the bed is comfortable, the air conditioner does its job, there's a bath which is nice. And also very important, the host is a very kind lady.
When I got there my arrival time was a bit uncertain, because I arrived from a 1600km bus ride (obviously with delays). I told this in advance to Sandra, the host, and she was very understanding and it was no problem at all. During my stay she asked whether everything was okay, which it was, and she was also very flexible with the check-out time. I had a wonderful long weekend in Buenos Aires, in this apartment, and I can only be very positive and grateful about it. Yay!