During the summer, rates are generally higher than any other time of the year, but you still fly cheaper as a courier than with other discount fares. In short, traveling as an air courier will save you hundreds of dollars on each trip you take. Some courier companies maintain a list of couriers who they can call at the last minute in the event of a cancellation, and let the courier fly free in exchange. Free flights are extremely rare, but super discounted last-minute flights are more common. Flights to the most popular destinations usually require at least a 2-week advance reservation, especially during the summer when advance booking can be 4 or 6 weeks or more to guarantee a seat.
Most people advance book in order to make sure they get the flights they want.
When courier companies are short of couriers for particular runs, the price usually starts dropping the closer it gets to the day or hour of takeoff. The length of stay which is permitted varies according to the ticket. Nearly every flight allows you to stay at least 7 days. Fixed stays of one week or two weeks are common on the European trips. Oriental and South American flights generally allow longer stays as a rule, and often require no minimum stay.