Unable to remove duplicates in SQL Query with JOIN and DISTINCT - sql-server

Question

I have a sort of abstract question with a real world example. I'm attempting to run a query that has an issue with the tables I am joining.
In my first draft of the query, if I add a Distinct and only have the one Inner Join needed, I sum up values that are correct.
The values I yield needed to be broken into 4 other totals depended on certain values. When I add the table in my query that has those values and add it to my join or where clause, it takes those totals and sums up each iteration of the value with the corresponding value.
My Query:
SELECT DISTINCT SUM(CASE WHEN Tax_Records.TaxValue = '0.06' THEN Bill_Summary.NonSalesTax
WHEN Tax_Records.TaxValue = '0.065' THEN Bill_Summary.NonSalesTax
WHEN Tax_Records.TaxValue = '0.07' THEN Bill_Summary.NonSalesTax
WHEN Tax_Records.TaxValue = '0.075' THEN Bill_Summary.NonSalesTax ELSE 0.0 END)
AS 'UnTaxable Sales'
FROM Order_Records INNER JOIN Bill_Summary ON Order_Records.RowNum = Bill_Summary.OrderNumID
LEFT JOIN Tax_Records ON Order_Records.OZipCode = Tax_Records.tZipCode
WHERE Order_Records.Date Between 'DATE' And 'DATE'
AND Order_Records.cState = 'state'
GROUP BY Tax_Records.TaxValue
My query runs correctly, but I get the wrong totals, if I remove the LEFT JOIN and it's corresponding items in the SELECT Statement i get the correct totals.
The Tax_Records table has no relation to any other table in the database so I know putting that in the Join will cause issues.
I changed my query to see why I'm getting the incorrect totals and it's because it will sum up a value depening on the cases on my select.
For instance there's an Bill_Summary with a value of 5, it will sum up 5 4 times, 1 for each tax value. So I know why it would do that, but I want to know how i can add the information from the Tax Table to my query to derive the 4 values from my original correct totals.
I've tried different JOINS, embedded SELECTs, and CTE's but nothing works correctly.
EDIT: All this data is coming from order's placed by customers.
What we want to see is the total value of Tax Collected from a certain State Tax in a period of 1 month. So for the month of March 1st to April 1st.
All the sales charged with a 6% Tax Rate Equals $50.
All the sales charged with a 6.5% Tax Rate Equals $65.
All the sales charged with a 7% Tax Rate equals $20.
All the Sales charged with a 7.5% Tax Rate equals $15.
If I run a query without joining the Tax_Records table, I get my correct total of $145.
No I want to show the total broken up into the 4 values as shown earlier by combining the Zip Codes found in the Order_Records table with the Zip Codes in the Tax_Records table.
What happens if I do that is let's say for the 7.5% Value, the total of those sales are $15. Where one sale was $8 and another $7, if I join the Tax_Records table, it runs the query to show that the total number of tax collected from the sales is $8 for 6%, 6.5%, 7%, and 7.5% same thing for the $7 order which then now shows my total for 7.5% to be $60 as opposed to $15 which it should be.

Answer 1

You can try like this
select * from demo;
+------+-------+
| id | des |
+------+-------+
| 1 | afgg |
| 2 | aaaaa |
+------+-------+
select * from test;
+------+---------+
| id | name |
+------+---------+
| 2 | aaaaa |
| 1 | assdasa |
+------+---------+
select id as id,des as description,'' as id,'' as name from demo UNION select '' as id ,''as description,id as id,name as name from test;
+------+-------------+------+---------+
| id | description | id | name |
+------+-------------+------+---------+
| 1 | afgg | | |
| 2 | aaaaa | | |
| | | 2 | aaaaa |
| | | 1 | assdasa |
+------+-------------+------+---------+
4 rows in set (0.00 sec)