Display the Payment Means window

 Goto Payment Means...

Ctrl + Y

Generate the Transaction Journal report

 Goto Transaction Journal...

Ctrl + J

Position the cursor in the Business Partner Code field

 Goto Business Partner Code

Ctrl + U

Move to the first row in the table

 Goto First Row

Ctrl + H

Move to the last row in the table

 Goto Last Row

Ctrl + E

Proceed to the Remarks field

 Goto Remarks

Ctrl + R

Copy the amount due to the Total or Amount fields in the Payment Means window

 Right Click Copy Balance Due

Ctrl + B in the Total or Amount field

Move to the next active field after you have changed the business partner name or a G/L account name in Checks for Payment

Ctrl + Shift + Tab