My customer is looking to create a customer credit term where a 35% prepayment is required on initial sales order entry and then the invoice when generated would be an installment of 35% due net 30 and 30% due net 60. Currently you can create Multiple percentage installment plans but cannot require the prepayment at sales order time but it does generate the two invoices with correct due dates. If I do single installment plan, it will allow prepayment but I only can have one due date for the balance due. 

I can see that you can create an installment plan with a day of zero for 35% but this does not require prepayment on sales order. Just creates an invoice due today. This also assumes I need to invoice immediately before shipping. 

I think I may be able to get creative with cash discount being 30 days with zero discount % and make the total terms net 60. But feel this could cause confusion. Trying not to customize too much if possible. Any ideas are appreciated!