Two states in the country make it possible to build a criminal pursuit authority that failed to enforce building codes. Texas does not have these laws even though I had personally lobbied legislators for over 20 years. Suffice it to say that I was not popular with building officials. The third-party called "inspectors" employed by the builder did not have any obligation to you. They have a contract with the builder. Not with you.
You do not even realize the parameters and limitations of the contract. If you are searching online for a building inspector then you can take a look here www.davidinspector.com/.
Many, third party inspectors are not even allowed to walk the surface of the roof, to open the breaker panel or to engage in any activity that may cause them to hurt. Also, third party inspectors often limited to certain items that he can check, say what part or shares he could not check out and to what limit the builder will receive information from inspectors.
Builders, almost all of them, are not interested in building quality, or even a safe structure. They are interested in maximizing profits and in getting past the ten-year structural warranty period of their law. That means you get a house built to be useful over the years ten.