But like he mentioned, they'll likely say no or have a negative reaction. 

If I stopped receiving them, I would view it quite negatively.

There are several places where a BRRRR deal can go wrong:Renovations go significantly over budgetYou can't rent it for what you thought leading to negative cash flowsYour ARV isn't high enough to refi, either because the market has changed or because you estimated incorrectlyYou no longer personally qualify for a refinanceNone of these are very big problems, if you're well capitalized.

I would be VERY RELUCTANT to do it at all because of the negative consequences and I would only do it if I was 1000%+ sure that if my deal(s) went bad, I had a back-up plan (or 3 back-up plans) to be able to prevent it from happening. 

DP, rehab paid for with cash, negative CF, are all examples of cost to the REI. 

I read on a different forum that the presence of a property manager negates any work I might do.

Just remember: most negative reviews are written by problematic tenants.

I see a lot of negative posts about Connected Investors from 2-4 years ago, but does the acquisition change investor opinions on its usefulness?  

I understand all except one part: If you go to the "results" tab at the bottom of the spreadsheet, line 27 where it shows the "profit at sale" row, I'm trying to understand why there are negative numbers for the profit?

Then, you deduct all the negatives from the property you are looking at to get an idea of what it is really worth.