I'm looking for tickets in despegar.com (a travel website for the American continent) and found out that a flight for just one person was about USD $350 incluiding all taxes, and I did the exact same search but instead of 1 person I chose 2 and the price for both tickets was USD $1200 (USD $600 each).
I thought this could be an error in the website, so I tried diferent dates and destinations getting the similar results.
Therefore I'm wondering if it is cheaper to buy airline tickets separately?
PS: The market price for the ticket I mentioned in the above example is about USD $600, so I'd love to take advantage of the USD $350 deal, but I'm afraid I might not find another ticket for my partner in the same flight.