Lancaster city limits short term rentals to only certain zones of the city so definitely look at the city website for that information.

With setting up LLCs would someone go to their Secretary of State website and do this?

Does anyone recommend knowledge sources on building a mobile home parks (websites, books, organizations, plans, etc..). 

If you can critically think, there's enough knowledge on this website to get you started for free.

She was very pleasant and explained that their website doesn’t work, which we thought was a bit unusual.

I was just on their website looking at the permit process:CityofSac-STR PermitLooks like 90 days max until you get a conditional use permit but still reading as it seems a little unclear:A short-term vacation rental may operate from a location that is not the operator's primary residence for a total of 90 days in a calendar year.

I wish there were more 'filters' / Criteria that you can filter by in real estate website to find what you're looking for. 

Start with the Arizona Department of Real Estate website and verify credentials, search licensees by entering their names. 

Dennis' dad and I actually tripped over something similar back in Chandler.. we learned to tap into city planning websites and even call the permit offices directly to get a real sense of their backlogs.

As you begin your REI journey here is one tip I have for you:Use this website as you are trying to narrow down the places you want to invest in. https://www.areavibes.com/Its awesome because it gives you a "total livability score" & you can compare different zip codes & streets to others.