The best time to buy tickets to Latin America is eighty days before the trip. The tickets are the most reasonably-priced as the cost is properly calculated, based on the demand.
The ultimate bargain would be a red-eye flight on Wednesday, at 1 am (local time). The middle-of-the-week flights are generally cheaper as there are not much passengers travelling.
If you haven’t set a date, search for tickets with a range of three to five days before and after the assumed one. You’ll definitely get lucky if you subscribe to price alerts. The web page will update you on the best rates for a destination of your choice. The most efficient option would be to log in to the website: all your preferences and search history will be saved and taken into account.
Be sure to look over the conditions to find out if the fare includes bag and luggage fees. In case it doesn’t, visit the airline’s website and check out if you can purchase those services. Avoid paying baggage fees at the airport - you will waste a ton of money.
Make certain you’ve chosen correct dates: low-cost carriers usually sell non-refundable cheap tickets.
If case you get yourself into a connecting flight situation, double check if you are on time for catching the next plane. Always keep in mind there could be delays, which could lead to you being late. Choose wisely when buying the connecting flight ticket; the best strategy would be buying tickets separately, carefully calculating the time between flights.
Last but not least: don’t forget about the visa. Always prepare for the trip with applying for a visa to the country of your destination, otherwise you efforts will be useless.