My husband and I thoroughly enjoyed our stay in Mexico City at RP 87 and we would highly recommend it.
It is a renovated building with modern amenities in the middle of an older area. Apartment 13 is situated in the back with 2 french doors balconies opening into the side of an unoccupied neighboring building which is in "ruins" (cactus has started to grow amongst the broken bricks) that gives it a rustic charm. It is quiet and nice because noise pollution is a big matter in CDMX. The layout of the place is awesome and thought 4 people would be a little tight....for the 2 of us it was great as I was able to allow my husband to sleep in while I got ready in the morning as the bathroom/kitchenette is on one end and the bedroom in on the other with a center living room / 2nd bedroom. It is nicely light and the overall decor is impeccable.
The 24 hour doorman was very nice and made checking in so easy given our flight delay which had us arriving at 10 pm.
The roof top was awesome...and as they say "instagram" worthy. We just didn't really have time to enjoy it but it was usually unused and quiet the couple of times we went up to take pictures.
The location is at the border to the centro historico and Tepito ( one of the barrios that people are advised not to venture into). I will say that in the early mornings and at night...the street of Republico de Peru (one way- one lane street) is deserted and it is quiet. However we felt safe to walk around heading to more tourists area. It is walkable - 10 minutes walk to Zocalo, 20 min. to Palacio de Bellas Artes and it is an easier street to access for Uber drivers. We were advised not to walk around at night by the doorman, but my husband and I are seasoned travelers and we walked around the immediate block when we arrived really late to get bottled water, hot dogs at several makeshift food stands (no restaurants in the immediate area) and were able to see some street artists creating some amazing work at 11 pm. It is safe just be aware of your surroundings. The best part about the location for us is that is is 2-3 doors down from Arena Coliseo where we say a lucha libre fight that is more for locals. It was awesome to just walk to it and walk back afterwards in 2 minutes.