5. Do you prefer pricing to be a la carte or all-in?

Ocean: Major ocean cruises can start at around $100 per person per day, which includes meals, entertainment, and lodging. From there, you can add on extras as your budget allows. So it's up to you how much you spend on alcohol, spa treatments, shore excursions, and specialty dining.

River: These cruises are ostensibly all-inclusive. Most lines include a daily excursion in your fare, which is typically a basic walking tour around a historic town. In addition, lunches and dinners often come with beer and wines, and Wi-Fi is increasingly becoming complimentary. Some also roll airfare, transfers, and pre- and post-cruise hotel stays.