I’d like to begin contacting some to secure financing/pre-approval letter for this potential property and I have a 10-page .pdf proposal ready to go for this property containing the financials/our experience/comps/pics all detailed for the HML.Anyone have a good experience/non-scam/reasonable HML they’d be willing to share/discuss?!

You could propose a short term seller financing note where there could be balloon payment to ensure the seller gets his money back sooner if he doesn't want to provide long term seller financing.

What you're proposing here is none of your own cash in the deal with a lower rate of return. 

your experience level, the number of properties you own, the number of STRs you have, the purchase price of this property, how long it's been listed, your income and expense projections, the terms you'd propose for seller financing, whether you're working with an agent, etc.you can't really know anything about the seller's financial condition from the listing, you're just guessing.the sellers agent will likely not be enthused about seller financing - it will be an uphill battle to get them to present it to the seller.

Saying this based on my 20+ years in taxation and 15+ years in software development prior to that.Well let me correct you on a few points:1) Haven't totally changed careers (at least not yet), at present I am primarily limited to addressing the US and foreign tax law consequences of cross border transfers of intellectual property in the context of merger and restructuring changes (mostly for Silicon Valley companies, but not exclusively).2) Never made the claim you suggest so you will need to take that straw man back to where you found it.3) Often during my time in the trenchs we had to come up with answers to questions pertaining to mere proposed legislation, and telling the client to wait a year until we figure it out was not an option.

I think we have a solid plan here, but would love some guidance on how to find these partners and how to create a good proposal for their loan!

You will not be able to use any income on the proposed cabins however until they are built and have a track record.  

OK - I'm skeptical you're going to buy for that much and get the proposed ARV

We have proposed to reimburse them $50 every month on electricity every month (which IMO is already a lot), but they refused. 

Lockhart is considered to be a front runner as they recently considered a substantial Chapter 313 tax incentive proposal, suggesting Micron or another large development has been eyeing the area closely.