President Obama makes a statement on Affordable Care Act in California. (Stephen Lam/Getty Images)

When a law requiring the uninsured to purchase health insurance takes effect on Jan. 1, 2014, the cost, the extensiveness of benefits and the number of competing insurance companies that opt in to the health care marketplaces will all depend on where a person lives, CNBC reports.

The Affordable Care Act mandating those marketplaces, also called exchanges, is a national law requiring the uninsured to purchase health insurance that will take effect Jan. 1.

But the cost of that insurance, how extensive the benefits are, and the number of insurance companies that will opt or be chosen to sell on those those marketplaces are all going to depend on the state a person happens to live in.

And even then, there will be variations within regions of some individual states, complicating an already complicated new system.

How well-or poorly-a given state's exchange functions in coming years in providing affordable health care to its population could directly affect how businesses view that state's attractiveness as a place to open up shop or expand.

"You're really at the mercy of what's going on in your state," said Jonathan Wu, co-founder of the price comparison web site

Read more at CNBC.