questions about credit management

Hi experts,

Pls help. Thx.

Q1: Is only static check proper for the below scenarios?

Scenario1: Customer pay deposit before production & pay the rest before delivery. The deposit always are entered in SAP system upon receipt of it.

Scenario 2: Customer need to pay before delivery. The prepayment may not be entered in SAP system immediately. In other words, it may await that billing document is created.

Q2: What are the meaning of "open receivables" as well as "net document value" in the below explanation from SAP ("check credit limit" in OVAK)? Appreciate illustrating.

"In static and dynamic credit checks, the credit exposure results from the total of open orders, open deliveries, OPEN RECEIVABLES and open items."

"In simple credit checks, the credit exposure results from the total of the NET DOCUMENT VALUE and the value of the open items."