Avianca, a budget-carrier based in Colombia via Booking.com have round trip airfares travelling from Miami (MIA) to Santiago Chile (SCL) for $ 379, making 1 stop both ways in Medellin for 1-3 hrs, both ways. These are economy light fares that will only allow you to have a personal item. There is no seat selection, no carry-on bag and no change.

Travel Availability:

Departs MIA: Aug 7, 9, 12, 14, 16, 19, 21
Returns: Aug 17, 22, 24, 27, 29, 31