Situation: rental house in CS with three students on lease. Paying equal rent, 1/3, 1/3, 1/3, year-round. Also responsible for equal shares of utilities. Over summer, one renter is gone home, still paying rent. But what is customary for handling of utilities, the cost of which is being generated by just two renters for the summer months? Common sense says utilities (not fixed costs) should be split equally between the two present renters for the two summer months. What say those of you who are B/CS landlords?