Filter aggregated table with direct query datasource

If you are doing Direct Query, you should probably write your own SQL statement that does the GROUP BY and a HAVING clause.

Question: Do you need the details of all sales, or just the summary? If you need details, consider wrapping it all in a stored procedure that takes as its input the 'less than threshold' value. (Hint: look at WINDOWING function in T-SQL as they will allow you to get an aggregate of a group for every detail record.)

Use the Advanced Options when setting up your data source. Put in:

EXEC dbo.MyProcedure 100

Then inspect the Power Query code it generated. 

Add a Power Query parameter.

Hack the dataset to substitute the literal "100" with the Power Query parameter.