The mobile home I would only want to keep for a few years to live in before building a new home. 

He said that you can still sell the home, and this would not hold you back in doing so. 

Would a HELOC or home equity loan on my personal home be a good idea to fund this?  

Otherwise, get a HELOC to access the equity to buy a home in AZ.

I had homes built in Florida and it took almost a year once all approved.

I would start by finding areas you actually WANT to live and go from there.Picking a place to call home simply because it has a real estate market that you feel will fit your goals is a great way to end up miserable. 

Quote from @Devin James: We’ve slowly been improving our homes the more we’ve built and the more feedback we get from our Buyers2021 – Added 8ft doors throughout the home2022 – Added a new elevation with stone in the front of the home2023 – NO carpet in the bedrooms, LVP throughout the home2024 – Added hurricane impact windows & new color options2025 – Adding Ceiling FansGotta be open to feedback and adjust accordinglyThis can be the difference of your home sitting on the market for 4 months vs 1 month where's the modifications and pictures?

Which size of home is typically perform best on a cost benefit analysis?

Both homes are now rented on two-year leases at $2,175/month.

What are the best areas of a single family house to renovate that will have the greatest improvement to home value?