So, this started on a positive note. The check-in and the communications around it was extremely efficient. Two days in, in the morning i spotted a cockroach crawling from under the bed. Stepping outside of the apartment (it's on the ground floor), there were tens of cockroaches outside (mostly dead). I immediately informed the hosts and they followed up saying that the building had just been fumigated (w/o their prior knowledge) and that was the reason that bugs all came out. to be fair, this didn't seem to be something that was under their control, but we all also got lucky that i'm not scared of bugs in general. i know some people would get slightly traumatized with such experience. i was planning to stay a few days more in mexico city than what i'd originally planned, but instead of extending my stay here, i just booked another airbnb in a much cleaner building. so, in summary, this is a very old building with a pest problem, there is always a chance (although it may be quite small) that the same thing happen to you.