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.

Do I have other products available to help with this?

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? 

The decision on how to vest title may come down to the best loan product available.  

@Michael GuydishFirst I would talk to lenders to get a feel for what products for my strategy.Then I would buy a value-add multifamily property for cash, then rehab it, get tenants at market rent, then refinance most of my money out, and do it again.

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...

I am all about efficiency and time blocking, and this "running around" was detrimental to my productivity.

I would absolutely spend a little more for more durable products.  

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