so you've booked your cruise and placed your deposit.  You're done til you make your final payment right ?  WRONG !    You need to check your cruise lines website at least once a week to see if there may have been a price drop.   I recently saved $200 because my cruise, for whatever reason, lowered its prices.  Yesterday, they were up by $100 again.   

Cruise prices fluctuate, and as long as you haven't made that final payment, you are eligible for for those savings.   Prices vary week to week, and there can be a several hundred dollar difference.  Why ?  Who knows.  Why is April 29th to Bermuda more than the week of the 22nd ?   Is the weather that much different ?

In short, it's up to you to be diligent and find your deals.  Don't leave everything up to your agent.  Just call or e mail them, tell them what you found, and they will look into it.  You may save some money, you may not.  It can't hurt to check.