Oh, believe me, I know how to get the best price. I am a TA, but find that we can get better pricing with my husband's military discount than with any TA rates. I always check past guest and resident rates, but military is still the best.
This past February, we scored a great deal on a Pack and Go rate, 3 nts. Fantasy, OV cabin for $185.00 complete. It was available about 4 weeks out, but that pricing only lasted for about 3 days.
I've never checked the Carnival website, so I don't know if the Pack and Go rates are available to the public, or only to TA's and PVP's, but if they are available to the public, and you live anywhere near a port and can travel at the last minute, you should keep your eyes on those rates.