Deposit on sales order

Hello,

My customer is using the Deposit on Order (payment means) in sales orders for some BPs. They would like to have an alert or an approbation triggered before adding a sales order if there is no deposit on order entered.

Is there a way to achieve this? Is the Paid amount entered in the Payment means/Deposit on order available somewhere in the database, even if the order and the down payment are not created yet?

Thanks a lot for your help.

Best regards,

Thibault