PerryChase,
Building is not as simple as you make it out to be in CA. All you are considering is building materials and labor. There is ALOT MORE THAN THAT! How about the roads and utility infrastructure that have to be built? How about all permits, governmental fees, affordable housing fees and environmental mitigation fees to name a few? A good rule of thumb I have heard is that land costs around here are typically at 1/3rd of the price of a home. I believe a buildable lot for a tract home in SD runs between 250K and 400K whereas land in TX is almost worthless in comparison. I’m sure someone on this forum has the expertise to step up with insight regarding this. Hopefully they will.