And what was the disposable income in 1908 when the median us income was $500. If buying a $30k car is out of reach for a family making $70k a year, then I find

And what was the disposable income in 1908 when the median us income was $500. If buying a $30k car is out of reach for a family making $70k a year, then I find it exceedingly hard to believe that a family making $500 in 1908 would be able to afford an $800 car. Microeconomic comparisons are very easy to tweak to achieve a conclusion determined a priori. Some goods and services like electronics, air travel, communication, and transport become orders of magnitude cheaper over the course of the 20th century. Others like healthcare and housing on average get more expensive, especially in the latter half of the 20th century. If you want to show lowering costs of living, weight the model towards the former. If you want to show a higher cost of living, weight the model towards the latter.