These days, Austin and San Francisco each have somewhere around 800,000 people, though the entire Bay Area is far more populous than the Texas Hill Country.
When comparing California with Texas, U-Haul says it all. To rent a 26-foot truck one way from San Francisco to Austin, the charge is $3,236, and yet the one-way charge for that same truck from Austin to San Francisco is just $399. Clearly what is happening is that far more people want to move from San Francisco to Austin than vice versa, so U-Haul has to pay its own employees to drive the empty trucks back from Texas.
On that basis, if you’re going to Detroit they should probably just give you a truck.