Well, it’s a good starting point to realize that property ownership is an imaginary concept, backed by social agreement and/or less social laws and contracts, which at some fundamental level are imperialistic violence.
Who are you going to pay to buy some certificate of ownership? Who would have the authority to sell it? What would it even mean? Should Jeff Bezos be able to buy a shell-shaped area of space around the Earth, and then charge a few for anyone who sends something through that space?
What frame of reference would one use to chart such ownership? Relative to the sun, I suppose, probably with a directional axis toward the center of the galaxy, or some distant star?
It reminds me of European empires signing agreements with each other to divide up parts of the Earth that they hadn’t even explored yet.
The idea of rich people using their excess money to claim sectors of space seems like a very nasty form of egoic greed to me.
On the other hand, perhaps a license or fee for using space might be worthwhile, if we had some benevolent and worthwhile and not corrupt agency to receive it. Because as corporations and egomaniac billionaires continue to send more and more crap into space, it has serious impacts in terms of resources used, environmental impacts, risks, and littering near-Earth space with obstacles and debris.
Check out http://www.stuffin.space/ !