The communication with Carlos before our trip went just fine. He is a quick responder and helped us with every request we had. Although Carlos was not there when we checked in -which was late in the evening- he made sure that we were able to pick up the keys nearby. Once inside the apartment the WIFI didn't work + it was super,super warm in the apartment. As we had a long flight it was kinda annoying, but Carlos gave us tips how to fix the WIFI and it also worked soon again. Nevertheless, the first nights -and pretty much all the nights- we had to open all the windows and leave the door to our room open, as the heat was really hard to deal with. We figured that it didn't come from the heaters but more from the pumps which run through every room. Those pumps caused a penetrating noise, which woke us up several times at night, cause it sound like somebody is breaking in to the apartment. Both my wife and I don't really have issues to sleep through noises but the heat combined with the pumps gave us a real rough time. The apartment itself is fine. The guestroom is good for a couple of nights, although the WIFI connection is poorely in there. You can find nice furniture in the living room but both kitchen and bathroom could use a makeover.
The area itself is nice and save. Also by night we never felt uncomfortable. It's only 5 minutes to the metro which takes you directly downtown. A big plus for the apartment.
Overall, the price for the apartment was justified and it was an okay place to stay in.