I vote for Baselane if you're OK with completely remote.

@Jose Julio, I joined only 2 weeks ago but already the "Tribe" has made it completely worth it to me, I have been teamed up with mentor(s) who ARE on my cash buyers list and help me add to it, they also put me onto the right title companies to use and contracts.

It's not a red flag in the sense that they are doing their best, it sounds like, to make you fully aware of it. 

It sounds like you've really thought through not just what a good deal looks like today, but the other factors that will contribute to a more long-term appreciating value.

Use the heloc to fund the construction, and then roll it over into a 2nd after completion.

That sounds good to me unless someone can articulate a better strategy for the area. 

Plus the added tax benefits to support my current situation ($120k a year as a "single" person with "0" dependents Uncle Sam definitely gets his cut) A home my family and I could use in the off seasons on vacation plus creating a unique experience with lifelong memories for our guests sounds great to me, regardless of whether it cash flows.

Can anybody suggest something smarter than my ideas of a complete beginner?

The processing time for a Davidson County, TN Owner-Occupied STR permit application can vary depending on several factors, including the completeness and accuracy of the application, the volume of applications received, and the workload of the permit office.According to the Metro Nashville Planning Department, the average processing time for Owner-Occupied STR permit applications is currently 4-6 weeks.

It sounds like you are working with a professional!