You don't want to turn away business but at the same time you do not want to allow your customers to exceed their credit limits. When that happens, you can put a customer On Hold as follows:
- Edit the customer
- Navigate to the Payment tab
- Check Hold Orders
- Click Yes to confirm.
- Click Save to save into the customer.
When a customer is on hold, you can still create a sales order but you will not be able to approve the order for shipment.
It is a good practice to add an Exception for Hold Orders in roles so that only certain edit this value.