Me and 2 friends (23 year old males) are traveling to South America from NYC for the first time for about 9 days in early November. We are looking to see Buenos Aires and one other location. We have considered Rio, Santiago, or Peru. We are very open to anything but things that are pluses are: (nightlife, beach & somewhat cost conscious). I was thinking that a multi-destination would be best (something like NYC--> BA --> Rio/Peru/Santiago --> NYC). Any advice is VERY appreciated as we do not know much about South America.