(See American Housing Survey Reveals Rise in Doubled-Up Households During Recession and For Many Families, Bad Times Require 'Doubling Up'.)And there was also a fear about jobs/income and credit.

3) Is there a usual or standard amount/percentage for the Option Fee, rent credits, and any other fees/charges?

If you haven't already, it would likely be worth your time to start having conversations with some of your local bankers / credit unions about your options around conventional financing vs.

SO what I guess I am saying is watch your DTI....Decide whether you want to have that line of credit available or if not. 

Are there circumstances where some investors might choose to use separate bank accounts and credit cards for each Series? 

Only thing to keep in mind is if the note is called be prepared to handle it appropriately. 

I'll use an example with similar numbers because I want to truly understand the reasoning here:On the high end, the interest rate would sit around 5.75%, at the cost of -.125 points (ultimately resulting in a lender credit of $164) and a P&I of $766 per month ... on the low end, the interest rate would be 5.375% at the cost of 1 point (around $1300) with P&I of $735 per month.Given that info, this is to say that if I planned on holding onto this property more than 42 months (that's $766-$735= $31 per month... then $1300/$31=41.94 months), then it would make financial sense to pay down the percentage rate up front at 1 point because beyond 42 months, I'd be saving money every month...

Closely related to cash reserves.Focus on those two main metrics, and one will be as prepared as they can be.

You may want to prepare a good pitch for it.  

Also, in step 3, is it possible to us a home equity line of credit?