I didn't realize it would be illegal (or morally questionable) to do this, which is precisely why I raised the question here before acting.

(Not a huge boost in income) What you are also getting, however, are tenants who have a nicer place to live.

Also, I would be helping people in a bad situation have stable housing which is a moral benefit, I just want to make sure I'm not falling into some big bureaucratic fiasco with nightmare tenants. 

You'll learn how to do things the best way while you're doing them and there are really only a few things that can't easily be fixed if you mess them up.Keep your morale up and keep your wife happy.

Sell now, Pay the taxes, and use cash to boost investing? 

I would like to help some one  to boost his wealth in real estate out there in MO or KS though.

I personally would never leverage that high and my morals prevent me from recommending it to clients... but it's out there and people are using it...

However, mine is dangerous + it is at times morally/ethically questionable.

I also have a very flexible private financier available, and I am wondering when to use them to pay off mortgages strategically to refinance and further boost my credit by paying off large lump sums relatively quickly and easily?

As I am a student, my funds are limited so right now I'm focusing on eliminating consumer debt, boosting my credit score, and saving some money to invest.