I stayed in the apartment for more than 3 weeks. I enjoyed my stay very much. The host agreed on early check-in/late check-out. Old buildings in Microcentro are nice looking but unfortunately they are noisy - no double-pane windows, etc. And I am a very light sleeper. I had a very nice sleep in this apartment - it is very quiet (a rare find in this area). Also, quite often listing photos look much better than reality. This is not the case here. What you see is what you get. Everything worked properly, including Wi-Fi. The kitchen even felt cozy. It was a good relaxed feeling to stay here. I asked the hosts for a few things, which were certainly not their direct responsibility to provide or help me with. But they went above and beyond helping me and I do appreciate that very much. I felt well taken care of.
If I need to make a small suggestion - add to the listing that the washing machine only does a cold wash (very minor thing).
I wouldn't hesitate for a second to stay here again.