The controversial, easily accessible debt monster was born. 

Invest in a stock or fund with a huge upside on appreciation (think AI / Robotics).  

Try to keep complexity and expenses low for your small business or you will spend a lot of time and cash feeding the monster.

I've read some cautionary tales about "monster homes" becoming management headaches.

What your considering here is some franken-sale "monster" of twisting these 2 into a manner neither was ever meant to be utilized as. 

Invest in a stock or fund with a huge upside on appreciation (think AI / Robotics).

AI / Robotics are pretty certain bets to me.  

Pay $1.5 million, tear it down, spend $3 million to build a brand new monster.

AI layoff is already happening Jason,  especially in tech sector, but not because of the job is replaced by the robot but because lot of tech company is moving direction from traditional business to AI sectol.

You are mentioning highly sought after parts of GA.I do commercial real estate over 20 years now specializing in NNN properties.Don't expect monster cash flow here for residential.