This is a very unique spot. The apartment is beautiful and really comfortable. Sandra and her assistant Yolanda were amazing hosts... I'd had a tough day when I arrived, so I was flustered and arrived a bit early. They were so helpful and understanding, they let me in and showed me around the neighborhood while the cleaning was finished. Sandra also let me stay an extra day for free, which was so amazingly kind. I would definitely come back.
Things to note: It's located above an antique/arts shopping area, which may be full on Saturdays, but is usually pretty quiet the rest of the week. The parking lot is public parking when you go into that first level, but there's a place on the left to buzz the downstairs lot, and you'll be let through to park in the lower level, private parking. The guards are really nice and will help you. The neighborhood is very busy, lots to do, tons of restaurants and bars. It really is the heart of the city.
Also, if you're driving in CDMX, keep in mind the Hoy No Circulo laws! (Spare the air days where you can't drive)