RE: Purchasing Airspace
Around here you do not own the airspace above your house. Not sure about the state of Washington, but I doubt it. And the writer of these articles often don't do any research before 'informing' us with their facts.
If they bought and sold the house, they can put building restrictions in the contract. And if this would hold up in court is a different story.
What they are saying is that you can own the airspace above someone else's property...