Avianca is offering some amazingly low fares for travel out of the U.S. with their Red Sale. You can fly from Miami to San Salvador for as little as $45 one way! These flights must be booked by September 26
Here’s an example of the Miami to San Salvador flight.
Note this books into the lowest fare class that has a lot of restrictions. If you book one fare class higher (M class) you can have fees waived for any changes you need to make. For the above example the M fare prices at $69 versus the $44 and includes seat selection, checked baggage and flight changes with no fees.