Usually non-refundable airline tickets are recommended. Non-refundable tickets are usually a fraction of the cost of refundable tickets and most non-refundable airline tickets are reusable (with a change fee) in the case of a cancellation. Please keep in mind that airline tickets are non-transferrable and must be used by the same person whose name is on the original ticket. Beware of "Basic Economy" tickets which are completely non-refundable – not reusable and not changeable – which are strongly discouraged.
