Book the Inca Trail ASAP with Tierras Vivas tour operator. There are two types of companies that will try and sell you an Inca trail package: registered tour operators and middle men, otherwise known as endosars. The registered tour operators are a small quantity that run, sell, and operate their own Inca Trail Tours.
All operators will ask you for a deposit which is generally NON-REFUNDABLE. It is non-refundable simply because the MINISTERIO DE CULTURA does not give back the agencies any money when a passenger cancels or changes a date. The operator then has to re-apply for a new permit if passengers change dates. Agency have different Payment methods.
There is no such thing as a WAITLIST / CANCELLATION LIST. If any agency / operator tells you that they can do this, they are simply not telling the truth and are operating illegally! Its as simple as if a passenger cancels their space is not given to anybody else - period!