It all adds up to an increasingly difficult financial balancing act. Even as their incomes begin to grow as their careers take root, 30-somethings are also in the highest-consumption phase of their lives, as they start families, consider buying a home for the first time or upgrading to a more family-friendly home, and improving their lifestyles as their incomes improve. Debt is a necessary part of meeting those challenges, but you have to handle it correctly.