Child support is set by a formula in the Michigan Child Support Guidelines. (You may want to download the Michigan Child Support Guidelines Manual to better understand this process.) The formula considers both parents' income, the number of children and their custodial arrangements, other child support payments, etc. But every-day financial responsibilities like rent/mortgages, utilities, credit card debts, etc. are not factored in.
The child's medical costs may also be included in the child support order. The Department of Health and Human Services (DHHS) MiChildSupport website has a free Child Support Calculator to help you estimate what will be ordered.