Shared supplies: who buys the toilet paper?
List the shared basics: toilet paper, soap, trash bags, dish soap, sponges, cleaner, and paper towels. Choose either a monthly household fund or a rotating buyer. Keep the list and receipts visible.
Set a spending limit for upgrades and specialty items. Someone who prefers a premium product can buy it personally unless the household agrees otherwise.
The system should make restocking automatic, not turn a small necessity into a personality test.