No but I do recommend that you search around before you purchase anything major as you would with insurance for house, car or travel or as you would before you buy a car etc. If you don't search around for the best prices then you will probably always accept the first price given to you with most things. It's the same with all things the more information you have the better equipped you will be to make a good decision. Hope this doesn't sound too much like a lecture but prices will often vary for the same cruise and throughout the year no one agent will always be the best. .... Neil.
Cruise tickets are no different to airline tickets, sale & demand. The cheap deals are normally the very first & the very last bookings. At other times, the price fluctuates inline with the level of interest in a particular cruise. It's unfair to name companies, as this site is run by a Travel Agent who specialises in Cruises. The Freephone numbers at the top right of this page. I'm not prepared to give my 'secrets' as to how to get a silly price, other than say, forget the brochures, the real deals have gone long before they go into print. Forget the High St Travel shops, use a cruise specialist or as a last resort be in a position to cruise at very short notice, ie within a week.
Try the week-end papers they are full of adds with offers and free phone numbers ,Avoid booking with cruise company direct,use the same methods you would buying a new car? best of luck.PS (Dont believe all the tales you get told).