This is a terrific place to stay! I was here for about 5 months (Jan through May, 2021), and it was a great little flat in a superb location. The neighbors are very friendly, but not intrusive. The elevator works great, and the resources of the city are easily available. As you exit the building, if you turn to the right you have an urban village atmosphere; if you turn left, you have the full city, including Chapultepec Park, and Roma, with its great restaurants and city life; If you walk straight, you hit the Paseo de la Reforma, with its spectacular promenades and city views.
The apartment itself is very quiet and peaceful. In the winter months, there is spectacular morning sunlight for 4-5 hours pretty much every day. It would be perfect for an artist's retreat.
Afonso is a great guy, and I recommend him to you highly. We communicated frequently through Whatsapp. His English is excellent, so there is no need to worry. Very communicative and helpful.
When I was there, pretty much 99.99% of the people were wearing masks. There was never any blowback about it of course. People take the Covid seriously, and yet the city functions normally.
Of course I had a choice of where to go. I am delighted that that I chose Mexico City, and specifically Alfonso's place. I recommend it to you highly, and if I ever return to CDMX, I hope to stay there again!