How much should I spend on rent or housing?

The classic guideline is to keep total housing costs at or below 28% of gross income, and many budgets target rent near 30% of take-home pay. Those are starting points, not laws: in a high-cost city you may run higher and offset it by spending less on transportation, while in a cheaper area staying well under frees up a lot for saving. Housing is your biggest, stickiest fixed cost, so a few percentage points here outweigh almost any latte-cutting elsewhere. The real test is whether, after housing, you can still hit your savings rate and cover everything else without strain. If rent crowds out saving, the apartment is too expensive regardless of the percentage. The home-affordability tool at wealthserene.com/tools/home-affordability can stress-test a number against your full budget.