All I can say is "amen, brother." Not following his first 3 general purpose lessons have cost me if not millions, at least many hundreds of thousands of dollars. I urge others to commit these to memory:

+Really understand something before you sign it.

+Ask all questions, dumb questions, hypothetical questions, extreme-scenario questions, what if questions, until you’re sure you really fully understand it as well as anyone on earth.

+It’s also very worth paying for an hour meeting with your accountant, and asking 100 questions there, too.