Budget makes a huge difference. You can get a no frills one week cruise on Princess for less than half of what a week will cost on Regent Seven Seas. A lot of the difference is due to Regents being all inclusive- booze, shore excursions, no tipping, airfare include, etc. Princess will charge extra for everything above room and board. Also Regents ships are smaller-750 passengers instead of 1500-2000.
