Try to find a solution any future issues like this.. 

He isn't ready to sell it yet but said if in the future, he'd talk to us before putting in on the market.

Thanks I would look to AirDNA for this - they have long had pretty good (guidance, not perfect) rentalizer solutions for projecting revenue, but have recently added good info on expected expenses and the property managers in the area (for at the very least coming up with expected operating / management costs) etc

Vanderbilt Health is one of the top heart transplant programs in the world, something many of us, myself included, may need in the future.

Generally, losses from your rental properties can only offset other passive income, and if your passive losses exceed your passive income, you carry forward the excess losses to future tax years.

Are you more interested in immediate cash flow, or are you willing to wait for potentially higher returns in the future?

Again I don't recommend using the HELOC to buy a LTR unless you can force appreciation heavily and refi out the HELOC.Regardless having a HELOC out is a good idea so you can be your own bank and fund a flip or BRRRR.I would go with the 300k as it might take time for me to find a deal and I would have more resources for bigger projects. 1% isn't too crazy... accesss to 100k is better IMO

You need to pass "material participation" test and personal use test, but that's for your future tax professional to explain.Yes, bonus depreciation is possible, but only on the current value of the personal property and land improvements.

My financial objective is Teak production and sales to India/China/Europe and also procuring physical locations that won't be for sale in the future.

Our project is similar to that larger-scale ADU project you are talking about.