I want to see if it's possible to put a new lien on this property so that he can't get a construction loan without paying me back. 

My wife is about to go back to school so she will not be contributing income as well as she will be tacking on a lot more debt to her initial student loans.

Getting prequalified for a loan is free (or should be) and usually is a soft credit check. 

Think of it this way, your own personal credit is tied to your SSN and you can improve it by utilizing credit whether that is credit cards, loans from a bank, or mortgages. 

Now assume you buy $350K home; put $25% down and take loan at 6 3/8 on $262,000;  Your payment is $1630/month or you're losing about $600/month all things being equal. 

Have you explored any bank statement loan options ? 

I also serve in the Georgia National Guard so I have access to the VA loan.

I've dabbled in traditional real estate since 2009 and investor RE loan products as well as conduct due diligence for private lenders leveraging their cash.

Talk to a few F&F lenders about % of ownership requirements to be the guarantor, and if there's a % of ownership which REQUIRES you to be a guarantor on the loan. you can avoid this headache by being strategic as to how the loan (and the LLC) is structured while you wait for your scores to improve again. 

I could put the 3.5% FHA loan route but not sure if I want to deal with FHA requirements.