To prevent situations when customers use your resources without paying for them, set up the rules that Business Manager will use to define when customers will get access to resources they order. For example, you can make the system create new hosting accounts in Panel after the corresponding invoices are issued and paid. Otherwise, to make your business more customer-friendly, you can let subscribers log in right after they place the order. Find instructions on configuring these rules in the section Setting Up Provisioning Policy.
However, to automate the processing of situations when your customers do not pay for the resources they use, define how the system should deal with such customers. You can specify when the system will send them notifications about due invoices, and block their access to the system. The section Defining How to Handle Unpaid Subscriptions explains how to set up these parameters.