Other than seeking out a Real Estate attorney what would you advise? 

It is to encourage investors who have the cash to flip and increase the value of these neighborhoods.

This actually increases your risk, not decreases it.

Only the most desperate renters would probably agree to live there so the price of the property would have to be dirt cheap and cost you as little money as possible in the rehab to make it worth the effort.Your gambling that the surrounding area will be gentrified in the next few years and increase the property values.If this was in Southern California I would say yes absolutely but,the ATL may be a little harder to wait for unless the population booms there in the next 5 years.

My long term real estate goal is to purchase rental properties that cash flow and create passive income that I can use to roll back into my investments and increase my portfolio. 

It seems to me like an easy 3% ish percent equity gain or a way to reduce the loan a little and increase cash flow a bit for almost nothing, that's my thought any way.  

(Seek areas under redevelopment where old owners are cashing out and new buyers are moving in for motivated sellers)Just one way to do it that have brought good results for us!

I joined this community to learn about real estate but more specifically how I can use real estate to passively increase my net worth.

Your's will have to be re calculated and increased accordingly to positively impact your ROI and cap rate.This is where most MHP investors fall far short of the mark.

I would go for the 3rd unit because you're going to be increasing your income and cashflow plus long term you'll have increased the value of the property by X amount of dollars which you could then apply to another property or toward those loans.