Yep. I'm adding 500sqft to my home in Silicon Valley and the cost will end up being more than I spent to buy the house 12 year ago.

Smaller jobs are more expensive per square foot because not all costs scale with size. Which is why you see all these godawful TJ Homes being built where they just rip out the house, build a 3 story structure (including basement) that takes every square inch of the lot.