I will say though, if you take a look objectively you might easily find a way to adjust the floor plan with just adding a wall or door.

You had better be on call 24/7 as your tenants will likely rarely sleep and will be digging holes in the walls looking for FBI cameras and copper wire to sell!     

With me as your agent you get to meet me at the house and I bring trash bags and we clean together all the stuff you don't want covered up in the walls.

Wall street is taking a commission on every transaction.

Not getting at least a title search is off the wall crazy.Land contracts/trusts will work but they are passive trusts and individual liability will continue. 

If the tenant identifies an area of moisture that may be causing growth we immediately address the source of the moisture, replace and damage building material (usually dry wall) and or use mold cleaning solutions/mold blocking primers as required. good luck

As far as say a vanity, always go back with at least the same size, will save you ton of work fixing walls, floors etc.

Goals are great, but you are throwing a lot of things at the wall right now.House hacking is a great option for a lot of people, but you already own a home and have equity in it.

And can I get away with only getting permits on new electric & moving plumbing, but demo,  erect walls myself and things like that?

For example we write exclusive use of the rental property includes use on two sides to the tree line, on one side to the rock wall and to the front curb.