Here are some of my opinions:In terms of rent to own, make sure  you are differentiating between rent to own and contract for deed.

This is not legal advice, just friendly information.Obviously, I'm biased, but an attorney should put that together.

I want to make this work and am so motivated, but I also don’t want to continue to wonder if what I’m doing isn’t legal 100%.

I would argue that the premium is valid due to the value I added to the property by getting the legal structure and agreements in place, then finding like-minded buyers.I'm looking for people to poke holes in my logic.

Learned a lot about the process while property is under contract (coordinating home inspections, appraisals, getting documentation to the lender, etc) I should have locked in my interest rate two weeks ago before they shot up recently!

This will be important for both your landlord and any legal follow-up.Notify Your Landlord: Since this is a rental property, your first step should be to inform the landlord.

- How should we structure the deal legally for a BRRRR strategy?

Add an additional two months for the contract to fall through due to buyer trying to negotiate like they are on the cast of Pawn Stars. 

Here in Florida text messages as legal documentation is a gray area.

Quote from @Alek Fort: Hello,If you are both in agreement on terms and %, then I would think almost any title company would be able to assist you with both the contract and closing.