Most people typically spend between 35% to 50% of income on housing and utilities. A crazy number that makes living at mom and dads seem a little nicer, I’m sure. In addition to rental or mortgage payments, this includes the cost to heat your home, electricity, telephone and cable service, and water. It would help if you considered other monthly expenses, including groceries, transportation costs such as parking or public transit, and entertainment costs such as alcohol or eating out.