However, if the place is operating as a rooming house - legal or not - when the appraiser reports back that there are 6 bedrooms (each with their own locks) and separate leases for each of the tenants, the lender will run away.Additionally, what @Ned Carey indicated about debt service not being included in NOI holds the same as practiced by investors in Canada.  

As your buying rental and your debt ration is your current Piti and what negative rental from the property your buying after calculation of thr piti & 25% for operating expense from 75% of potential income. 

If the loan is set up amortize for the 30 year on 500k then the refi, debt service is only going to be approx 2k monthly.

We live in Louisiana and squatter's rights and adverse possession I'm not sure of, but SBA has never tried to evict or posted any foreclosure papers.

The law does not outline such specifics and there is little case law to rely on.We would definitely not recommend that you JV with your IRA while obtaining debt-financing personally.  

If you have and are sure you are still underwater, continue to monitor and pay down debt so when the day comes that you can get out from under it, you are ready to take advantage of the opportunity.

All depends on Your Global Debt to Income.

To some degree, if I don't know what I don't know then I can't properly evaluate another party who possess knowledge I don't know about.

AP cases that involve color of title are unique in terms of how they are possessed.

I have saved $30,000 dollars and have no debts accept for $19,500 student loans that I don't have to start paying off until December with a 4.5% interest rate ($220/month).