This really depends on three things: which airline, if it's a direct flight or if there are stops, and how far in advance you book the trip.
If you book a flight up to a year in advance, you will likely be paying between $500 and $800 dollars round-trip. If you book the day of, it could be between $1500 and $2000 roundtrip. If you book somewhere in between that, it'll probably be $600-1,000.
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