Each state has its own regulations.
Some are quite relaxed, while others are very militant.
Personally, I would think that with 9 layers, after family consumption is subtracted, there would not be so many eggs for sale to warrant any extensive 'infrastructure' setup.
One thing many states frown on is using leftover cartons. If the cartons are marked with a producer's name/brand, and any sizing/grading info, these
should be 'whited out'so as to NOT imply that these are "Safeway Grade A Large".
Here is a Colorado guideline for cleaning/sanitizing eggs.
Home flock egg washing