But, even though I own another home besides this one, make a mid-six figure income and have excellent job security (cybersecurity), and a DTI ratio of 13% - I can't qualify because my FICO score (612) is too low.

I'm completely new to real estate investing and I'm looking for a second source of income. 

Is it to payoff the property and have income without mortgage payments?

I plan to expand in real-estate investing by acquiring more properties to provide supplemental income apart from my primary job.  

I understand that margins might be tighter, and income may not be as attractive as the STR market, but we also don't have the capital, time, or competitive edge to deal in the STR market in the 30A corridor right now.Don't get me wrong...

Buy and hold for rental income?

Wouldn't the very nature of doing REI'ing (Rehab and sell) qualify as earned income?

At this point, she may be counting on you for the income on this particular deal.But I would still put the proposal out there to her James !!!

Depreciation recapture, income taxes on the depreciation taken, are due upon the sale of the property, regardless of sale price.  

This property was my only source of income.