She informed me on December 1st that she was expecting a job offer requiring a January move-out, which she received on December 12th.

It can affect estimated replacement cost and therefore the amount of coverage recommended/required.  

Cash invested: $80,000 Acquired this property Sub-to as a quick flip with minimal repairs required.

Chicago would also require a $0 exempt stamp,Just a FYI, Any deed recorded in Chicago will require a City of Chicago water cert.Directly from my title guy.But like John said your attorney should be able to tell you exactly.

Just be cautious of DTI (debt-to-income) ratios when qualifying for additional loans if you’re relying on projected STR income—most lenders require at least 12 months of rental history.

If it was me...I'd check with zoning to find out how many dwelling units I could build, and I'd find what the requirements are for those units (type of house, height and setback restrictions, etc.).Then I'd find out what local builders think the cost to construct would be - just get a cost estimate per square foot for 2 or 3 different levels of finish.

Is it required to have a brokers license or be listed under someone that does? 

It's critically important to make sure you know the exact zoning in regards to minimum stay requirements before you go too deep into a property.

After I reached that goal, I set a new goal of 3x the required income for financial independence with the intent of giving 2/3 of it to charity.I don't believe in leaving a massive legacy for my children.

I can come up with only about a third of the required down payment.