I think a very important document is a list of all the stuff that DOESN'T WORK.  With detailed descriptions of stuff that didn't work (like Paul's original fuel system), the reason it didn't work, and some ways to fix it. 
Guess we'll need a web site where we could post all this important info ... Jim S.

John Slade wrote:

a "checklist" and make it available to the builder long
before the team might be called to inspect.
That's an important point. We make a lot of decisions as we go along, many of which are expensive and / or very time consuming. The resistance to change increases (reasonably) the closer we get to being done. Guidance is needed along the way, not just the day before first flight.