Base fare is only one line
Ancillary fees can change which option is actually cheaper.
Schedule has value
A better departure time or nonstop route may reduce hotel, meal or ground-transport costs.
Fare conditions matter
Change and cancellation terms can be materially different.
Book from a source you can support later
Understand who is responsible if the itinerary changes.
Verify before you go. Weather, entry rules, advisories, transport schedules, prices and local conditions can change. Use this page to structure your decision, then verify the current details that affect your specific trip.