I agree with John as the TA is the best bet but in today's world you at least have the ability to look for alternatives.
What I meant by bulk pricing is the TA group can decide to sell a set number of cabins and this allows the cruise line to reduce the overall pricing which in turn allows the TA to reduce the package.
Much like if you get xn friends together for xn cabins and act as the buyer then you will get a free cabin which allows you to reduce the overall price.
Be aware though of internet pricing that does not include port fees and taxes plus possible CC charge and processing fee. Then add up the total. Also ensure the Internet company is bonded with your local / country travel insurance.
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