CASE function in SQL Query Table

CASE function in SQL Query Table

I have 2 Data Tables coming from different sources syncing into the same workspace.  I have several columns (Columns A – G) from Data Table 1 and 1 Column from Data Table 2 (Column B) that I want to show up in a Query table.

DT 1 and DT 2 are joined by a common column (Column J in DT1 and Column A in DT 2).

This I am able to accomplish in a Query Table.  Here is where I get stuck.  I want a conditional formula that is based on DT2.Column B.  The CASE WHEN in the code below isn’t working…..

​Can anyone tell me what I'm doing wrong here?

SELECT 
    t1."JC_STD_ALT_GL" AS `Store Code`,
    t1."Initials" AS `BDM`,
    t1."JC_PROJ_MANAGER" AS `PM`,
    t1."JC_DATE" AS `Booking Date`,
    t1."Customer_Number",
    t1."JC_CUSTOMER_NAME" AS `Customer Name`,
    t1."JC_JI_LINE1" AS `Job Name`,
    t1."JC_APPROVED_AMT" AS `Net Contract`,
    t1."Orig Total Budget",
    t1."GM$",
    t1."GM%",
    t1.`Base Job #`,
    t1."Store Name",
    t2."New or Existing"
    CASE
    WHEN t2."New or Existing"='Existing' THEN t1."GM$"*.035
    WHEN t2."New or Existing"='New' THEN t1."GM$"*.14
    END AS `BDM Commission`
FROM 
    "Bookings Detail tbl" AS t1
JOIN 
    "Accounts" AS t2
ON 
    t1."Customer_Number" = t2."Structure Account Number";