Rent Affordability

Each uses a different percentage of income and handles other debts differently: 33% of Income applies a flat one-third to gross income with no debt adjustment, while Rent Cap (30% Style) and 50% Minus Other both start from a percentage of income and then subtract Other Fixed Monthly obligations before landing on a number. The percentage chosen and whether other debts are subtracted first can easily produce a spread of several hundred dollars between the three figures on the same income.

No -- Other Fixed Monthly reduces Rent Cap (30% Style) and 50% Minus Other, both of which explicitly subtract it, but the 33% of Income figure ignores it completely, since that benchmark is calculated purely from Monthly Gross Income. That makes 33% of Income the most optimistic of the three whenever you have meaningful other debt, since it ignores that debt entirely.

Raising Max Rent % of Income directly raises the Rent Cap (30% Style) figure, since that percentage is multiplied straight against Monthly Gross Income before subtracting Other Fixed Monthly. It has no effect on 33% of Income or 50% Minus Other, both of which use their own fixed percentages (33% and 50% respectively) regardless of what you set the adjustable slider to.

Using the lowest of the three as your ceiling is the more conservative approach, since it accounts for the debt obligations that the flat 33% rule ignores and uses a more cautious percentage than the 50% figure. Landlords and property managers frequently apply their own stricter screening rule (commonly requiring gross income at least 2.5x to 3x the monthly rent), so treat all three figures here as a planning ceiling for your own budget, not a guarantee of what a landlord will actually approve.