I beleive right now it is just over 800,000 sqft with plans to build another 200,000sqft on to it. From what i heard, they have a moveable wall that can get pushed to extend the size of the building.
I do not know the answer to square footage... it is a warehouse. Yes, very large. It is not a store front. Uline supplies businesses primarily and allows random customers to pick up at the warehouse to save on shipping. I ordered my moving kit via phone and it was ready for pick up same day. There are signs guiding to correct location to pick up. Hope this helps :D
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