I can take occasional trips into the City at that point.I do think some days I could be retired in much of the rest of the country. 

Tornadoes occasionally but rarely in Birmingham (More common in the West of the state).  

With a bike and the occasional uber you are fine there.

Hoover, bluff park, cahaba heights will occasionally have a good deal pop up on the listings, but they go real fast.

I occasionally need to have an additional document signed and I use DocuSign for that.

Real estate agents are usually good for people who only buy one home or the occasional property, but if you're doing this full time you already know the marketing, opening escrow, title reports, closing, etc, etc.

@Chris Bird It can make sense in so many scenarios, but always requires an awareness of all the moving parts and, occasionally, a crystal ball.

Regardless, if you are going to pay off early, please be sure to leave yourself some liquidity for the occasional speed bump that life throws at you. 

I visit the Twin Cities occasionally and go with a buddy to a local shooting range there.

The principle is what you need to take away ( Use HELOC money to pay your bills, deposit your income back to HELOC balance, Occasionally use HELOC money to pay extra principle on a loan, and repeat).You are gonna have the extra bill of the HELOC payment but Long Term you will have a lot a interest that you're defeating by paying principle off early.