in 2005, the last actual data I could find that lists 2 income households, the median income was $75,293, assuming that income kept pace with inflation that would be $98,562 today not 125K,
Such a family would not want to spend more than 49K total on their cars. so that is 1 car for 49K or 2 for 24K
and that IMO should be the extreme absolute limit
And it seems obviously extravagant to me for a middle class family to have two new cars. One maybe, but two? But even so, by the formula, the family can afford two $30K cars.