Put it up for bids on
www.cruisecompete.com
I saved $2,000 on a 32 day Seabourn cruise compared to what Seabourn charged on their own web site. There is a section on the website where you can add that you are an AMEX Platinum card holder. My experience is that there will be one or two agencies that will be able to offer that benefit. Usually, I get an average of 6 bids and they come in very quick, usually within 24 hours. Some bids will show up within an hour.