They've seen the peaks and valleys (08 crash and now post covid crash) and they've done unbelievably well investing there. 

Class C is more work than class B, but if managed well can do great.  

Credit and background checks, minimum 620 score, income verification, and limit the number of people living in the home.Tenant Own Homes is popular as well, you own the land and collect lot rent!

Lots has changed over the years.Managing it yourself from a distance can be done, but it will require your team to be built and for you to have back up strategies if guests need attention and you're unavailable. 

I am an agent and own a short term rental mgmnt company so am very familiar with the STR rules and regulations as well as the best areas for that strategy locally. 

An agent can represent a seller or a buyer even if they don't own the property, but they have to have the owner's approval.If the "seller" doesn't meet deadlines, it's probably a wholesaler who is having diffculties of some sort with the actual seller.So, either I misunderstand what is actually going on, or some information has not been conveyed.

i want to do buy and flip and buy and hold as well. 

In long run could have some negative consequencesalso Is it just residential or commercial as well?    

The type of the neighborhoods where his properties were located didn't fit in with my plan but he did well and the purchase costs were low.

I've been thinking about ADUs as well, so I will keep that as an option.