with hard money you're going to pay interest on the loan, which can be pretty hefty, especially if the rehab goes longer than planned. 

I plan on transferring my properties under an LLC due to partnerships and etc

.- Use cost segregation studies to expedite depreciation of your properties to offset large income gains.Entity Structure- Choose appropriate legal structure (LLC, partnership, or S corporation) with consideration for different tax implications.Tax Credits- Explore available credits, like energy-efficient or historic rehabilitation credits.Qualified Business Income (QBI) Deduction- Check eligibility for QBI deduction, providing up to a 20% deduction on qualified business income.Record Keeping- Keep accurate and organized records for tax compliance and audits.State and Local Taxes- Consider varying state and local tax implications, including property and income tax rates.Tax Planning- Engage in proactive tax planning, consulting with professionals for a comprehensive strategy.Tax Changes- Stay informed about changes in federal, state, and local tax laws affecting real estate investments.Remember to consult a real estate tax professional for personalized advice based on your specific situation.

We were not educated in the work and financial planning for such an undertaking.

The Deal: - Need a growth story that is believable (value-add plan makes sense in context of asset and market.- Financial models need to  assume exit cap rates are the same or higher than purchase cap rates.- Comps support both acquisition and exit cap rate assumptions.

for a unique deal like this they might be more open, considering finding funding isn't as straight forward. just also be sure you have a backup plan for this property... what if they don't renew their lease at the end?

We plan on building on the property in a couple of years but may go ahead and clear the trees soon.  

Originally, we planned for me to handle the down payment with my HELOC, and my partner would pay me 50% of the HELOC payment each month while getting his own mortgage for the rest (75% of the purchase price).But it turns out he couldn't snag a mortgage for the full amount.

Alternatively you could possibly look into an SBA loan if you plan to owner occupy one of the properties (depending on your current role and whether its W2 or etc.) 

The folks I know who work with them seem happy, but I know you have to pay for their strategic planning before they will onboard you as a client.