| Nonstop Flights: Austin to Liberia, Costa Rica $238 r/t [November-December] (limited dates) â American Airlines American Airlines has round-trip flights from Austin (AUS) to Liberia, Costa Rica (LIR) for $238, NONSTOP. Flights November to December. Departures on Tuesday, Thursday, and Saturday. Extended weekends available. Click for more details and booking links Nonstop Flights: Austin to Liberia, Costa Rica $238 r/t [November-December] (limited dates) â American Airlines . | 
