Originally Posted by Xero

"May" is the key word here. To me, the word "may" means that there is a chance for the price to change. But there is also a chance that it will not. It should have been the employee's responsibility to inform the customer of the change.

In contracts, there is a concept called "Contra proferentem". When there is ambiguity in a contract, you interpret it in factor of the party that did not write the contract. Marriott is who wrote the contract, not the customer. Marriott can change/clarify its wording at anytime. In this case, that means the contract should be interpreted in a way that favors the customer.