Housing for the Whole World in USD 317 Trillion

150 housing units: 60 in Asia, Middle East and Australia; 40 in Africa; 40 in the Americas; 10 in Europe.
60,000,000 (10ft by 10ft) rooms x 150 = 9,000,000,000 = Entire Population of World in 2050.
source: http://www.geohive.com/earth/pop_continent.aspx

Each Housing Unit (Land + Buidings) =  USD 2.11 Trillion

Land = USD 10 Billion
13,774 acres = 20,000ft x 30,000ft = USD 10,000,000,000 = USD 10 Billion
source: http://www.findaproperty.com/displaystory.aspx?edid=00&salerent=0&storyid=23197

Buildings = USD 2.1 Trillion
4,000 rooms x 15 floors x 1,000 buildings = 60,000,000 rooms
60,000,000 rooms x 100 sq ft x USD 350 = USD 2,100,000,000,000 = USD 2.1 Trillion
source: http://www.trulia.com/voices/Market_Conditions/What_is_the_construction_cost_per_square_foot_for_-31246

Total Cost: USD 2.11 Trillion x 150 = USD 316.5 Trillion

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