Probably Iran's most sought-after prize is its vast oil reserves.
Marin Katusa, a portfolio manager and author of the book "The Colder War," expects Russian, Chinese and Indian national oil companies to be major players, while Sunni Gulf states will be frozen out of Shiite Iran. The end of sanctions also presents an opportunity for international oilfield services firms such as Schlumberger.
But U.S.-based, internationally focused oil field services firms that operate overseas subsidiaries, such as Halliburton, are also poised to be early movers, he said.
"I think that the American companies will be welcomed in Iran," he said, adding, "This is not a game for junior companies, and I call juniors anything below a billion-dollar market cap. This is a big-money game."
Even if further U.S. sanctions relief finds support on Capitol Hill, risk-averse banks, particularly U.S. institutions, may not be on board, Wolber said. So-called snap-back provisions—which allow world powers to restore sanctions if Iran violates the terms of the deal—will also make banks hesitant to participate in transactions, he added.
"There may be a lag time in terms of what's allowed commercially and what's feasible via the financial system," Wolber said.