This also makes it eligible for bonus depreciation (60% in 2024) or Section 179 deductions if criteria are met.However, if the RV is permanently affixed to the campground site and functions as part of the real estate, it may fall under residential property classification and depreciate over 27.5 years.

Just be mindful that you can't 1031 a personal residence but it might be eligible for capital gain exclusion from section 121.

Hope all that makes sense. 2) LLC-B contributes $5875 towards retirement --> tax deduction what type of contribution is this?

Window AC units can indeed be treated as tangible personal property with a 5-yr life and be bonus-depreciated or deducted under Section 179. 

I can deduct the interest, but it gets added it B and C vs A?

(I'm guessing) my deduction would go further next year.

Although many properties with a specific zoning code are technically eligible, they would be subject to an extensive waitlist that could last years.

Eligibility: Not all loans are eligible for recasting.

I am a retired USAF 20 year career and I have never used my VA loan eligibility, because it is a bad loan.  

Google USDA property eligibility and click the Guaranteed search.