Without it the lease would remain between the previous owner and the tenant, you would not even be entitled to rent...

Then you should go back later in the evening like around 10 p.m.

Zero-percent business credit lines can be a great tool to fund renovations, repairs, and even serve as gap or bridge funding when working on a BRRRR deal.

Yes - and even when its out there its typically impossible to qualify (need high rate and high DSCR and typically would have to qualify as a LTR - so almost a unicorn or in a really bad market)

I have three single family rentals for three years and I now have my first horror story.

Depending on what your investing goals are you want to looking into self directed IRA vs. checkbook IRA or even better if you qualify Solo 401k.

Or that does not even matter that my SSN is attached to EIN of child LLC, and the taxes still pass the taxes to the parent LLC (if I set child LLC to be a pass through entity)?

If they owned the house within the past 5 years, it will count as an asset even if it's been sold. 

Unless you are hurting bad for a tenant, I would say no right off the bat, it sucks going some time without a tenant, but it sucks even worse when you cant get them out of the house and then they destroy it.

As others have mentioned, you typically need some liquid capital to get a deal done even if a hard money lender was funding 100% of the deal for you.