Would use “affordable” to compare house, or housing market.
Housing code at California has to meet requirement of earthquake. Hence house is stronger and expensive. Brick and concrete are popular in building materials.
Housing at New England area is traditional. Also uses more stone, brick and concrete. Houses at Boston/NY area and Bay area are similar, in pricing.
I believe living costs/or index of Boston area and Bay area are highest in USA.
Houses at Taxes are much cheaper. It’s well known.
When earning is about 100k, an affordable house could be pricing 300k instead of one million.