Three roommates, three different income levels, and a house full of shared bills that used to cause quiet resentment every month. The fix was a simple spreadsheet that splits fixed costs like rent evenly but splits variable costs like groceries and utilities proportionally to income, agreed on once at the start.
Each person logs what they paid directly, the sheet calculates who owes who, and we settle up once a month instead of constantly Venmo-ing each other for small amounts. The proportional split took some upfront conversation to agree on, but it’s removed almost all the friction that used to come with an even three-way split.
It’s not complicated, just a few formulas, but having it written down and agreed on ahead of time did more than any conversation could have.