It would be a shame to sell the 4 plex just to buy another house (probably a single family from what I understand). 

By looking at her credit report, it is clear to me she’d probably have issues paying her rent, but that’s where I didn’t know how much you all rely on a co-signer for.

Although if you use only your own money and lend only to investors you will probably get away with it.

In my case, we do no deny tenants based on bankruptcy (only evictions), and this tenant would probably get a thumbs up, pending employment verification etc). 

It seems to me that even in the perfect situation, where I get paid like 12% interest rate with no chance of default, and I get a HELOC with around 6% interest rate, I'm going to have to pay taxes on the interest I collect, but I cannot write off the interest I pay, and it will probably not be worth it.

The other is much lower but is a fixer upper that would probably require work that would bring the total cost to be $140,000 with the addition of the money to do repairs. 

@Paul Sandhu I can't blame her, if I was her I'd probably tell you the same thing!  

But probably not. 

@Russell Brazil thanks, I'm probably naturally a bit more conservative that many, so I try to think about different risk factors. 

A title company would probably give you some real estate contracts that are the standard ones used in NE that realtors use.