There's a fantastic article by William Bohl at HardwoodParoxysm.com today called "The Evolving Nature of NBA Ownership" that's a must-read if you are interested in learning more about the history of team owners, how they made their fortunes and how much of it they had to spend to own a NBA team.
via the article.
Half the NBA’s teams have changed hands in the past decade, and 11 new primary ownership groups have joined the league since 2010. Between 1998 and 2011, sale prices hovered steadily between $200 million and $400 million, the lone exceptions being the Wizards ($550 million to Ted Leonsis, but the sale included the Verizon Center) and the Warriors (who were the subject of a four-pronged bidding war, which eventually drove up the price to $450 million, paid by Joe Lacob, Peter Guber and their investors). In 2012, Vivek Renadive bought the Sacramento Kings for a record $534 million, a record soon broken when Herb Kohl sold the Milwaukee Bucks, and broken again when Donald Sterling was forced to sell the Clippers.
It isn’t just the price tags that are changing; the sources of owners’ wealth have changed as well.