I visited this house during my one day in Mexico City flying home from Yucatán. The required reservation over the website did not work, therefore I just went there and was lucky to get a spot in a tour if though in Spanish.
The house is interesting: very clear but still full of asymmetries and surprises. Very modern but full of crosses as architectural elements and in old paintings. Very bright and open, but still protected from the outside world by high walls. It has many brightly painted walls and the predominant color is pink. It came to my mind I f Barragán was gay. A short glance in his biography seems rather to support this. Though the house is a museum you cannot enter all the rooms and it seems Barragán gave it in his will to his last architect partner. Perhaps it is him who still lives there.
The price for the visit is high with 300 Pesos. Our guide was ok but not great. He was not too happy to answer questions and looked from time to time into his chat messages...
While an interesting visit I am not sure if it is unique enough to justify the inscription and based on my internet search I am not even sure if it is his best work. The Cuadra San Cristobal in Mexico City seems a strong competition
Neighbouring to the museum in Nr. 20 is another house by Barragán that you can enter from 10-13.30h for 200 Pesos if somebody is there to open the door. You can see a big garden and glance quite easily into the rooms designed by Barragán. But the garden is not well cared for. There are non of the strong colours of his own house or they have disappeared over time. While it is certainly a treat for great fans coming from the Museum it may be a disappointment for the average WHS-hunter.