The affordability conversation has focused heavily on vehicle prices and monthly payments.

The next problem may be bigger: total transportation cost.

Gasoline prices are hitting record Labor Day levels nationally as crude oil moves above $90 per barrel. At the same time, a stronger-than-expected jobs report has pushed interest rates higher and increased expectations that the Federal Reserve could keep borrowing costs elevated—or even raise rates again.

That puts dealers in a difficult position.

A customer can potentially absorb a higher vehicle payment. They can potentially absorb higher fuel costs. Insurance has already become more expensive in many markets.

But what happens when all three move against the customer simultaneously?

Maybe the industry needs to stop defining affordability by monthly payment alone and start considering the customer’s total monthly transportation expense.

If that number keeps rising, which vehicles and customers get squeezed first?