How can we minimize tax liability when pulling these funds and using for the house?

I'm eager to get started, and I've already determined I want to do BRRRR (which as I understand, if I play my cards right, should cost me no out of pocket money).Should I just focus on minimizing expenses as much as I can to get that safety net quicker?

If you are doing a full rehab maintenance should be minimal.

I suggest a grass variety that needs minimal watering and mowing, since this would appeal to tenants with pets as well. 

The management hours are minimal, about 1.5 hours per month per property for the bookkeeping, scheduling repairs, etc. 

People want to get away to a coast, lake, or mountain area, escape from their homes they are locked up in for months, but do it with minimal risk of COVID. 

How do people minimize risk here?

You are right - that would be a great way to minimize that risk.

Is there any minimal amount?

I personally don't hit the 70% rule every time, usually because they are larger deals (600k ARV) where there is still a very healthy profit, and we've come to know our process, the area, and what sells which minimizes our risk.