COST OF LIVING OVERVIEW. Our cost of living indices are based on a US average of 100. An amount below 100 means California, California is cheaper than the US average. A cost of living index above 100 means California, California is more expensive.Overall, California, California cost of living is 150.60.ur cost of living indices are based on a US average of 100. An amount below 100 means California, California is cheaper than the US average.