I am creating a custom module to allow customers to pay in installments using only credit cards payment method.
I have added the blocks with the Grand total like Paying now, paying later and have the interface ready where customers can view their paid installments.
I want to change the amount customer is paying according to their selected installments say Total order is $1000 and customer choose to pay in two installments i.e $500 as first and $500 as second.
I dont want to change the grand total, I want to change the Paid Amount in Orders, invoices, emails everything related to orders.
I managed to change the grand total and base grand total using sales_order_place_before event through order observer. It changed the grand total amont but the amount charged was the full amount only.
What is required or what scenario I should follow to accomplish the task. I am really stuck with this and hitting the wall.
Any help will be greatly appreciated.