Different Costs for Industry Complexes

Hello,

I found that building industry complexes in some provinces is more expensive than in others.

E.G: in Wilmington it costs 7500 goods, 10000 steel, 5000 or rare materials and 20000 dollar

in Savannah its much cheaper! 2000 goods, 1500 steel and only 7500 dollars.

I couldnt find a pattern, so what is the logic for this?