I would like to buy a camper and park it in my back yard and then rent out or Airbnb my house while living in my camper.

I’m never using for rent signs in the yard again !

You don't know if you are not the person behind that door simply and only because that path has not been chosen for you, and you've chosen to ignore that possibility.I wonder you have ever said to yourself, looking at one of your evicted tenants as they pick through their forlorn belongings on the curb, trying to salvage something, anything of their broken lives, "There but for the grace of the universe go I."

They keep the yard clean and help me keep an eye on the place. 

It is VERY, VERY hard to get out a RTO tenant who destroys the place, never cares for the yard, moves in extra folks, subleases, pays late or partial amounts, etc. as the judge looks at it more as the tenants home than yours in some places.4. 

I also have questions: should I allow access to the basement, the yard, the attic?

A upstairs unit, downstairs unit duplex loses some of those advantages (possible loss of yard, someone living above or below you).

There are a bunch of trees in the yard that shade parts of the roof, can't even install satellite TV because of the trees.

I have already driven the area and have a list of homes that have neglected yards and deferred maintenance on the outside of the home.

Lower level has 2 bedrooms, family room w/ 2nd fireplace, and access to private back yard and spacious garage.