It has been suggested to call these people 1hr prior to the showing time to verify they still plan to come.

The best documentation in the world won't help you strategically plan how to use your 1031 opportunity if the QI isn't responsive to in a timely manner.Demonstrated experience and nationwide footprint I would toss out as the two most important criteria. 

Is there anything I can do to ideally get them to not list the house and sell to me, I’m assuming there might not be many options, especially since the sister and I had agreed on a price that was below market value given I was planning to invest money to remodel the home and was planning to honor his wishes of not having the home knocked down to make a townhome or new home.

Your brain is going haywire and your body is simply trying to do all the changes and still fit into your skin.

As a newbie it would be wise to have a game plan in place before you start your journey.

What was your Plan?

There are pros and cons to each, but the way I see it, if you have a set strategy you plan on implementing over and over again, then you need to find a direct lender who specializes in that investing strategy.

I live in NY, and plan to invest in FL.

You can also do a Deferred Sales Trust, again all depends on what you are planning to do with the proceeds of the sale.

I plan to replace this before flip is complete.