Twenty-five percent is the recommended amount for mortgage or rent payments. Once you include all other home expenses (utilities, upkeep, home owners insurance, and taxes) it shouldn't ideally be more than 33%.
Car payments, gas, and other all expenses are separate. Your monthly car payment shouldn't be more than 20%. That leaves 47% for gas, vehicle upkeep, health insurance, food, entertainment, and savings.
Who actually lives this way I don't know, but I would like to (and not live like a pauper, of course).
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