How is justice to be served between two wives in paying the bills for housing and mobile phones, given that they live in two separate homes?

The husband must be just between his two wives in the division (of time/attention), and provide each wife her right to maintenance according to what is customary. Equality is not obligatory in electricity and phone expenses, as what is considered in maintenance is sufficiency according to what is customary. One wife's needs may be greater than the other's, so she should be spent upon according to her need. It is permissible for the husband to favor one of his wives in maintenance beyond her obligatory sufficiency, and this is not considered contrary to the enjoined justice, even though equality is more preferable.