Question 1

How do you fairly split rent between rooms of different sizes?

Accepted Answer

Splitting the total evenly overpays whoever gets the worst room, and splitting it by square footage assumes everyone values space the same way. The alternative is to let each person say what the rooms are worth to them, then choose the assignment and the prices together so that nobody prefers anyone else's room at the price it ended up carrying. That property is called envy-freeness, and a solution always exists.

Question 2

What does envy-free rent division mean?

Accepted Answer

An allocation is envy-free when no participant would rather have someone else's room at that room's price, judged by their own stated numbers. It gives "I got outbid" a real answer: you were offered that room at that price and your own numbers said you preferred your room and the difference in cash.

Question 3

How do you decide who gets the master bedroom?

Accepted Answer

Not by seniority, a coin flip, or who booked first. A ballot carries two separate signals: rank decides who is placed where, and price adjustments decide what a room costs the group. Someone can say the master is genuinely the best room and still rank it last because they do not want to pay for it alone, and the mechanism reads those as the different statements they are.

Question 4

Is Room Selector 5000 free?

Accepted Answer

Yes. Creating a trip, ranking beds and reading results are free, with no account beyond a one-time email verification link. There is a voluntary support link that buys no features and changes no result.

Room Selector 5000

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