Every Blade of Grass has a memory provoking post regarding the true current dimensions of 2x4s.
Washington State circa 1970s had Certified Public Adjusters, licensed and regulated by the state; that would represent insured vs. their insurer on claims, mainly fire loss.
During one of my unemployment stints in construction, I solicited claims for one of these adjusters on a commission basis.
A very old Masonic Hall was hit by arson and suffered a significant amount of damage. We were able to solicit the claim. The adjuster killed the insurance company. The building was built with real 2x4s, 4x4s, etc. That was what the insurance company insured, with no wavier for changes in dimensions, and that is what they had to pay to replace. The proposed settlement was in the high five figures. After the Certified Public Adjuster finished his work, the settlement was in the lower six figures.
My commission on his commission caught up a lot of bills and replenished the savings account.
A valuable lesson for me. In addition to the most welcome commission, the necessity to look below the surface and consider the history of a project saved my ass a few times in the years ahead.
As an example, check the county records to see who is the actual owner of a piece of land before building on it for someone else.