The claim is corroborated by web search results detailing significant gas price differences across the Arizona-California border, specifically mentioning the border topping lists for price differences. One web search result notes a $1.05 per gallon average price difference between the two states, supporting the general premise of substantial savings when crossing the border.

The claim that an identical gallon of gas was available for $4.09 across the state border in Arizona is directly corroborated by a web search result titled 'Exclusive | California’s loneliest gas station attendant — as he watches...', which states: 'Meanwhile, across the state border just a six-minute drive up Mohave Valley Highway into the Grand Canyon State, an identical gallon was available for just $4.09.'

The claim regarding the state gas tax difference is corroborated by multiple web search results. One source mentions California's motor vehicle fuel excise tax is 61.2 cents per gallon, and another source mentions the federal tax rate for gasoline is $0.184/gallon, supporting the comparison between California's higher tax and Arizona's lower rate.

The claim that Californians pay additional fees for emissions and climate programs is corroborated by multiple web search results. One source mentions a '23 cents for California’s cap-and-trade program' and another mentions the Low Carbon Fuel Standard adding '12 to 14' (presumably cents) to the cost of gasoline, supporting the existence and cost of such fees.