I am very curious at the STR loophole for tax purposes.

I will wait until we've held the lot for at least 1 year to avoid additional taxes owed per my CPA's advice.

Plug it all into BNBCalc and share it so others can give you feedback- look at the tax savings via the "short-term loophole" at the bottom and learn how that functions as well as it can be a huge aspect of your investment.

From Wikipedia, Alabama has the second lowest property taxes behind Hawaii.2.

I would never rent a house with a pool due to maintenance issues as well as liability. 

She had no use for it and the taxes were becoming a burden.

I think the tax benefits combined with building equity is the goal, cash flow is not a major issue thankfully with our household w2 income.

I would want to separate the liability from my brokerage business and my real estate flipping business.

What apps should I use for setting up a system to invest in tax deeds?

Since you requested any book recommendations, I wanted to point you towards Tax Free Wealth by Tom Wheelwright.