Deposits also depend on the length of the cruise. FAQs has them all, but the easy ones are
$150 pp 4 days
$200 pp 5 days
$250 7 day
I think $300 for a 8 day
If you are only seeing $250 pp deposits, you must be only looking at 7 day cruises?
as mentioned above there are some that are larger, like alaska I believe might be more.