Yes, Partner Billing Rules and Customer Price Books can be used together.
A Partner can create both Partner Billing Rules and Custom Price Book and apply it to manipulate the pricing that a Customer sees within their tenant.
The order of processing is as follows:
As Custom Price Books are applied after Partner Billing Rules, it is possible to create a Custom Line Item Billing Rule and use the Custom Price Book to manipulate that Billing Rule entry.
Example:
Partner Billing Rule - Custom Line Item:
Custom Price Book:
<RuleGroup startDate=\"2022-01-01\" endDate=\"2022-12-31\" payerAccounts=\"xxxxxx\">
<BillingRule name=\"Change General Credit Billing Rule\" includeDataTransfer=\"true\">
<BasicBillingRule billingAdjustment=\"-10000.00\" billingRuleType=\"fixedRate\"/>
<Product productName=\"Customer General Credits\">
<LineItemDescription contains=\"Customer General Credits\"/>
</Product>
</BillingRule>
</RuleGroup>
In this example, a Custom Line Item called 'Customer General Credits' is created by the Partner Billing Rule with a value of $0.01. Custom Price Book is then used to change this value to -$10,000.