TLDR:

Trade centers had a huge asbestos problem. Anyone who thought of buying that property had to be an idiot due to it being a skyscraper filled with asbestos and would cost an insane amount to remove it. The second video is him saying he had designs made to build wtc7 back in 2000. Shortly before the planes hit the twin towers he bought the buildings and he took out insurance on the trade centers in the manner of billions of dollars.

Much much more can be inferred from the videos.