ICF
I know some are against modular. In the northeast they are very popular. Not due to cost. Mostly to do with the builders. By the time the subdivision gets approved, through the many layers of review, possibly an environmental impact statement, complaints from the neighbors that the "bucolic" surroundings that they built thier house in are being ruined ( They did not buy the surrounding land) and this is if it is zoned for what you are building. To change zoning it is worse. As soon as someone annouces a review of a large subdivision someone will push for a moratorium on new permits. Once the builder gets this through, Excavates, puts in services, foundation. It makes sense to have a modular trucked in. Not much on cost savings. But it saves the time that a lawyer could put a stop work on it. once they are approved by the town and dropped in, that is that. So up here in commie country New york, where the people that bought the new house last month are pushing to save the open space and make thiers the last house built. At the expense of the owners of the open space.
As for me , I am going to rebuild. Thanks to all these commies, the value of my exising "house" (more like a shack) is valuable. I am looking at the ICF basement and side walls. Can be covered by anything ( I like brick) Essentially a reinforced concrete house about 5% more expensive than stick built, quiet and energy efficient. I just have to come up with plans, a project timeline, location and cost of concrete pumping crews and equipment. All in a high labor litigous state. Wonderfull.