Both times that we have stayed in Buenos Aires we have rented a flat in Palermo. The first was in a more modern building and was generally a bit better, but both were fine. They were both in normal apartment buildings, living alongside local Porteños.
The second place was a bit older, with one of those lifts where you have to open an internal and external door and if you don't close both properly it won't move. Thankfully, as we were on the seventh floor, it always worked.
The flat owners obviously weren't too keen on fixing things. There was the collapsed leg on the bed bit of the sofa bed and the glued on oven door handle that came off when the oven heated up and melted the glue. But generally their solution of choice appeared to be sellotape, with light fittings, the dodgy leg of the bedside table, and the loo seat all taped back together only partially effectively. That said, very thing was generally OK, and we were perfectly happy there for a month.
What really amused us though was something that presumably the caretaker, but possibly another resident did in the lobby. They had obviously been having a problem with someone dropping cigarette butts from one of the upper floors into a small courtyard area. We came back on day to find a notice on the mirror telling people to stop, with the notice surrounded by the offending butts sellotaped to the mirror.
We thought that was funny enough, but the next week the problem had escalated from cigarettes to used condoms. So there was a new notice on the mirror, and yes, a condom stuck above it. I have no idea whether it was the actual discarded used one, or a fresh one for demonstration purposes. I didn't really want to get close enough to find out!
Clearly though the offender still didn't get the message, as a few days later there was another notice saying that the police had been called and would be coming out to interview everyone on the relevant part of the building. This one was even translated into English, presumably so that there could be no mistake if the guilty party was a non local resident.
Thankfully our flat wasn't in the part where all this was going on, so we weren't suspects and didn't have to see the police. I don't know if they did actually come out or not - I can't see the UK police having time for that somehow - or whether the offender admitted their crimes, but it must have put a stop to it as there were no more notices after that.