What if someone wants a more expensive hotel?

If one person wants a luxury suite, they must pay the difference between the agreed-upon baseline accommodation cost and the luxury upgrade.

How do we handle the person who buys all the groceries?

Log every grocery run in your expense app immediately. Never leave it to 'we'll figure it out at the end,' as memory is notoriously bad for group math.

How to Split Vacation Costs Fairly Among Family Members with Different Incomes

Avoid resentment by using a tiered contribution system based on a percentage of income rather than an equal split. Discuss finances before booking anything to ensure every family member feels comfortable with the chosen budget.

Establish the 'Core Cost' baseline. Calculate the unavoidable shared costs for the trip: accommodation, rental cars, and shared groceries. Exclude individual expenses like airfare or personal shopping.
Set a percentage-based contribution. Instead of splitting the total by the number of people, decide that everyone contributes a set percentage of their monthly disposable income to the 'travel fund.' This ensures those with higher incomes pay more while protecting the lower-income earners.
Separate individual expenses. Agree that individual expenses like fancy cocktails, excursions, or private transport are paid for individually. This prevents the 'I didn't even want that activity' conflict.
Use an app for real-time tracking. Use an app like Splitwise to log every group expense as it happens. Set the default split to 'unequal' based on your pre-agreed percentages.

What if someone wants a more expensive hotel?: If one person wants a luxury suite, they must pay the difference between the agreed-upon baseline accommodation cost and the luxury upgrade.
How do we handle the person who buys all the groceries?: Log every grocery run in your expense app immediately. Never leave it to 'we'll figure it out at the end,' as memory is notoriously bad for group math.