Been there, done that.....Now you can keep the existing ground level garage and install new structure above to carry the new load.

The only commercial level appliance I have is a 36” range, it’s kind of hard to justify having anything else in a regular home.

Are there regulations at the Federal or state (Michigan) level restricting the number of rental occupants per bedroom and siblings per bedroom?

I doubt it is for tax reasons, since IL and NC are not much different at the state level.

This is a classic raised ranch (bi-level), 3x2, at about 1500 sq feet, built-in 1995. 

Also varies greatly on what class of homes you have / they have and the income level. 

The dollar return isn’t everything; as alluded to, the time required to manage the investment and stress level should be taken into account.

First off my goal;My line of work is changing at some point at no fault of my own (finance) and what I do (which pays six figures) is the target replacement level income TO WALK AWAY FROM THE JOB. 

That could also determine his comfort level in the area and if you'll want to start there.

On a makro level David is not wrong: we have seen this very clearly the last 2 years and above all it is the housing supply that is making it difficult.