Housing costs vary widely across the U.S., with Hawaii having the highest index at 302.4, far above the national average of 100. Other expensive states include Massachusetts, D.C., California, and New York. Lower-cost housing is found mainly in the South and Midwest, with Oklahoma at the lowest index of 66.9. Large states like Texas, Georgia, and North Carolina also have below-average housing costs, while Florida is near the national average.