We stayed at Carlos' place for a summer trip to CDMX and were generally pleased with everything. The location is great - it's walking distance to the Chapultepec park and La Zona Rosa, but it's in a relatively quiet neighborhood that felt safe.
The room itself was nicely decorated and well-stocked for travelers. While the space was not terribly large, it was arranged and divided well so you hardly noticed. There were also a lot of nice, small touches like the tiling in the kitchen and the designs carved into the wood furniture. The kitchen had a stove, sink, Nespresso machine and basic cooking supplies. It was also stocked with a few snacks, a bottle of wine, and coffee.
Our only complaint is that the bed is a bit smaller than what we're used to. I'm pretty tall, so that may only be an issue for tall people, but if you're planning to share the bed with someone you should be comfortable getting close! It did look like the couch might have pulled out into a second bed, but we didn't try so I'm not sure.
Overall, we enjoyed the experience and would recommend it!