Somewhere between shorts and a tank top and a suit and tie.

I'm assuming that the old sink wasn't vented before and therefore you can't tie into an existing vent system? 

However, I will have also tied up a chunk of liquidity in the deal, so it's difficult for me to truly see that as cash flow.  

You haven't got a dime of your own money into it (heloc qualifies as your own money because its usually tied to your equity;  even if it's just a signature line, that could be considered 'bad debt' if it's got a variable rate, and has no amortization paying down the principle).  

I'm not as gray as it shows in my profile picture and don't usually wear a tie!

My income is guaranteed and is tied to the federal government not local market.Not trying to slam you here just saying most people don't look at the bigger picture and when factoring all variables Chicago will beat any A market every time.

Must I be tied to his entire family.....?

Obviously my capital would not be tied up for several months, but is there any other benefit to financing a piece of my investment instead of paying all cash?

Example ours is a 3 way partnership, we each have a debit card tied to our checking account.

Once 1 property was paid off I planed to make double payments on the other.House (A) I currently owe about $61,000 with a 2.5% fixed interest rate with a 5 year balloon note I just refinanced into.House (B) I currently owe $102,000 at 5.0% fixed interest rate at 30 years.I own 5 acres of land(C) free and clear in Beebe Arkansas that I am currently living on that's tied up in House(A) worth about $25,000.