3) if there’s decent equity after his and others’ sweat and material, and he wants to take on the challenge, he’s back at step 1; seeking real legal counsel on his standing with the lender(s). 

There is no legal way around that.

@Zachary Sexton; @Ali Boone; @Russell Brazil; @Jordan Moorhead; @Matt Shields I don't necessarily agree with the idea that there is a specific "advice" from BP and that it is risky... like others have posted before, everyone has their level of comfort with risk and that's what they should go with.But I do have an issue with BP Podcasts - both the original one and the new Money one - are we ever going to see a guest that doesn't have their own website, their own blog, is trying to sell/promote something for his/her own gain and that hasn't in fact already interviewed the BP people in their own podcast?

@Daniel Caraway You need to find out what the legal use is shown at the city's Building Department.

If you ask for a change be prepared to reimburse the bank the legal costs to research your question.  

I would also look for a way to LEGALLY get them out of the rental as soon as possible and get someone qualified, mature, and stable in there.

@Matthew Olszak What is the date on which winter begins legally?

As a result, I understand the financial and legal aspects of real estate but cannot say I know the first thing about actually being a real estate investor.

We refinanced our house several years ago to decrease the length of our loan to 15 years which increased our monthly payment a little but has allowed us to make faster gains toward the pay off. 

When the money is out of the TSP I am assuming it is no longer acquiring the gains/losses from sitting in its fund.