As someone who has had a home built, and nearly all my friends and acquaintances report the same thing, having a 1% error on information in this business would mean not a 10x but a 50x improvement over the current practice in the field.

If nobody is supervising building documents all the time during the process, every house would be a pile of rubbish. And even when you do stuff stills creeps in and has to be redone, often more than once.