I just tried out the current cost of living calculator to compare my current city in Idaho to San Diego, CA. A San Diego resident making $100,000 in 2003 can live as comfortably on $53,000 in Pocatello, ID.
The feds essentially let you take the state income tax off your AGI, so the extra I have to pay to Idaho comes off to some extent on the federal return.
Idaho sales tax is 6% this year. It was only 5% when I first arrived. I was paying 7.75% in San Diego. I bought a truck last year. $19,000+tax. My sales tax was almost 2% lower against $19,000. My registration was only $56 compared to a likely assessment over $500 from the CA DMV based on value. I have 3 vehicles with car insurance rates that are cumulatively less than a single vehicle cost me when I had it parked at my parent's home in Chula Vista. Much lower rates of theft and vandalism compared with being next to the Mexican border.