What I am saying is that if that building in the picture is 20-30 feet tall, it could be approximately 100 x 120 footprint which is 12,000 sq.ft.
Look at the picture again.
If that building is 300 x 400 feet (=120,000), from its proportions it is about 75 feet tall. I seriously doubt that an industrial park building would be a hi-rise like that.
Maybe it is a picture of the old building?
Again, It looks to me that this an image of a 12,000 sq ft building on a 3 acre lot,
Unfortunately, no scale indicated in picture, but I base my estimate on the vehicle in the driveway being circa 20 feet.