This is my first post and I’ve been diving into real estate investing for a few weeks now; just reading, listening, and watching REI information non-stop.

Non-super conforming mortgages remain unaffected.You can verify this with section 4501.10 of the Freddie Mac "Single-Family Seller/Servicer Guide", updated just a few weeks ago: Feb 6th 2019. 

The selling agent said he was now going with the other offer because it didn’t require an inspection.Is it legal to accept an offer and then receive a different one and go with the later after the original deal was verbally accepted?

Offer contingency rests heavily on condition of the park and the interiors of the abandoned homes...and assessing whether these homes can be repaired—and if so, will it cost me an arm and a leg to repair 1 or 5 or 10 of them.Obviously, this is a distressed, non-performing MHP, which has a ton of risk. 

@Randy SmithYes but the financing must be non-recourse (as well as subject to the Solo 401k real estate rules that apply generally).

Unless they are non recourse loans, then by all means borrow away.

My tax advisor stated Box 1 "Rents" and the church tax advisor states Box 7 "Non-Employee Compensation" since it's not actual rent for the church but considered a donation to them.

Keep it professional and short and non-negotiable.

There are ways around that for example if you used seller financing then you would be signing a non recourse loan.   

Self-directed IRA If you are self-employed with no full-time w-2 employees, you can set up a Solo 401k & rollover funds from a non-Roth IRA as a tax-free direct rollover and then invest in real estate.A Solo 401k has several advantages as compared to a Self-Directed IRA including the following which specifically apply to your situation: Unlike a Self-directed IRA, you can have the account for the Solo 401k at a bank or brokerage that does not charge maintenance fees and where you will have checkbook control.Unlike a Self-directed IRA, if you use leverage (which must be non-recourse financing in either case) to acquire real estate with your Solo 401k the income will not be subject to Unrelated Debt Finance Income taxGeneral Considerations Re Investing Retirement Funds in Real Estate:1.