OK, for your second revised example, you could create three custom columns in Power Query:
Percent Difference = Number.Abs(([Estimated Dollars] - [Actual Dollars]) / [Estimated Dollars]) Difference = Number.Abs([Estimated Dollars] - [Actual Dollars]) Tolerance = if [Percent Difference] > .1 then "Out of Tolerance" else if [Difference] < 10 then "Review Estimate" else "Within Tolerance"
For the first one, the MAX query, that is something that is trivial in DAX but not necessarily in "M" code.