This would require a land use attorney as every jurisdiction is very different.

But I guess I'm not sure what content to go for that will explain to me what I need to know before making any investment, the different types of investments, how hiring people works, If I should go work for someone who is already an investor, and if I do I'm not even sure what they would even need or if investors even hire anyone who's new.

House hacking is a completely different analysis in my mind because it's also providing you shelter. 

If you plan to use a "co-host" and they run your listing - that's different. 

What do you look for to ID different areas where that might not be the case?

We'll outline the core challenges and opportunities this presents to investors, developers, and property managers alike.Analyzing the Impacts: Here, we delve into the effects of this surge on different market participants.

If you are paying some of the utilities, then that is a different story as those costs will go up with more people living there.If you do have them move in, add them to the lease and make it clear that if the original tenants move, the son and his family also have to move out. 

Attend a local meetup that attracts different investors.

I assume I can deduct it, they cant and they pay tax on the difference in interest between the primary mortgage and my personal loan with them?

Don't commingle between your different entities.