Bank account wise, create a separate one. 100 different reasons to do so (e.g. commingling issues, cross liability issues, etc). 

Maybe you should cross-post this in the Success Stories forum - most newbie introductions don't include 5 deals / 9 doors ;) Already a rock star! 

I have space for it in the existing panel.2. 8/2 NM wire, per kin manufacturer's recommendation (60 ft run)3. 6-50 NEMA outletGiven the power amount we're talking about here and the price of the kiln I'm putting in, I'm trying to make sure I cross all the i's and dot all the t's. 

Yes, I believe the term is "Cross Collateralization", a few lenders I have worked with do them. 

Some of the basic benefits are transaction speed and the ability for low cost, cross-border payments. 

Other than the mls, I would look on zillow/trulia and cross reference tcad but that is a snapshot at best. 

Finding a mortgage tends to get a bit harder, and rates are often a tad higher, once you cross the thresholds of having 4 and 6 properties with mortgages.

Then I look at a number of sources such as Trulia to see the crime in the area, and I'll also cross-reference rentals on the market (my strategy is buy and hold).

As such, in an effort to satisfy my own curiosity, is it ridiculous for me to consider cross-collateralizing two vehicles to secure a loan and get started with a house-hackable duplex or other small investment property?

It crosses my mind some days to just sell it but another home would be just as much so not much gain.