United has round-trip flights from Austin (AUS) to Liberia, Costa Rica (LIR) for $315-$339 with a connection. Flights in May, August, September, October, November, December, January, and February. Extended weekends available. Origin/Destination reversible. Holiday blackouts.
United’s “Basic Economy” fares do not allow for a free carry-on bag. Only a personal item (like a small laptop bag) is free. Seats are randomly assigned for free prior to boarding.
The personal item size on United is smaller (9 x 10 x 17 inches) than Frontier or Spirit (8 x 13 x 18 inches).