Carolina,Recoleta Carolina said:Cujodu,
It takes heroic effort to be from the U.S. and live in Buenos Aires! All foreigners have it tough but Americans have it worse. I have never been able to completely figure it out but it doesn't really matter. That's just the way it is.
I would pass on the suggestion to tell your administrator (unless you know your administrator very well). Usually, the administrator and encargado are in bed together. And, even if they are not, they are not going to go against each other for a foreigner.
Just keep your area clean. Keep to yourself. Don't give the people in the building any justified reason to complain about you (they are going to find many unjustified reasons on their own to complain about you). If the people in the building are nasty I can guarantee you that things are not going to improve. They will either stay the same as they are now or they will get worse over time.
I would consider moving if you are renting. If you own, I would seriously consider selling. But, obviously, that is easier said than done. And, I wouldn't do anything before really checking out the next building, neighbors, administrator, and encargado very carefully. They can all make your life miserable.
My building is the building from hell. It makes all of your stories sound like a day at the beach! Most foreigners have their own horror stories but usually do not admit it or else they have perfected the art of looking the other way over time.
There is nothing anywhere in the world that would make you feel more miserable and worthless than not standing for your rights and accepting (if ) any type of discrimination.