I can't say enough good things about my stay at María José's apartment on Reforma. I stayed in this AirBnB for about six weeks while preparing for my doctoral exams, and it was a wonderful place to call home. The apartment is spacious, clean, and had all of the amenities that you'd need for a long term stay, including a washer and dryer on the bottom floor (pro tip if you choose this location: the dryer takes US quarters, so bring a few to use during your stay if you'll be washing clothing, though you can also purchase them from the doorman). I also cooked many of my meals at home and had no problem doing so. The apartment was well-equipped with pans and cookware, and there's a grocery store about a 10-minute walk away.
I should also mention location -- it is truly perfectly situated. It's pretty much equidistant to Chapultepec Park and the surrounding areas (including Polanco and Condesa - about a 30-45 minute walk) as well as the Centro Histórico (also about a 30 minute walk), so I walked pretty much everywhere and barely took Ubers, except at night. I also could comfortably walk to most locations in Roma Norte and la Juárez in under 30 minutes. So if you want to be walking distance to many different neighborhoods in CDMX, this is a great place to be.
Finally, I want to give a special shout out to María José, who was an incredible host. Her communication was so prompt and attentive, and when a light went out in the kitchen early on in my stay, she had someone there the next morning to change it for me. I felt like if anything went wrong (though my whole stay was very smooth), she'd be available to help me right away. As a single woman staying by myself, that meant a lot to me. I also felt really safe staying in this building, and the doormen were so kind. Truly a wonderful place, and I hope to stay here again on my subsequent visits to CDMX!