Spending 30% or 40% of your family's income on a car is bad financial planning. If "the narrative" indicates you "should" be able to spend that much, you need

Spending 30% or 40% of your family's income on a car is bad financial planning. If "the narrative" indicates you "should" be able to spend that much, you need a new narrative. Ideally one that will not send you into penury.