For example: state of California with 8 sub-categories
Scenario 1 :
In Module 1 exercise, if CATEGORIES fall under the same keyword - we don't recommend you create separate pages for it. You can attack that group of keywords in same page.
Make sure the 8 sub-categories are valid.
Scenario 2: When you do Module 1 exercise and find out these 8 categories don't belong together in same group. In that case we recommend creating separate pages for that.
When starting out, 8 global pages are fine.
Once your main site is complete and you think that there is enough revenue to be made in any of your sub-categories, THEN you may expand those sub-categories and build their city pages.