Why do you think anything with a government stamp is automatically 10x the price? It's not because of people wanting smaller government. Smaller government is about localizing procurement down to the smallest workable level.
Making a huge tender to build these environmentally safe houses for everyone would mean only the biggest and most expensive companies could compete in the 10 year long bidding process. Making a tender for 10 houses for the local poor in your village would be free in comparison, and those 10 houses would be ready before the poor die of old age.