Custom Sales by Customer Detailed Report > Amount is Compounding when Address Book is used as a filter.

It is standard system behavior when running a custom Sales report – Detail (and Address Book is added as a filter) that if the customer record has more than one address book row, the report will generate multiple results.

Example, invoice amount is $500, then customer has three addresses listed in the address book, the report would show the invoice amount to be $1,500. 

Solution

To show the correct amount in the report, another filter should be added (either Default Billing or Default Shipping).

1. Navigate to Reports > Sales > Sales by Customer Detailed Report
2. Under Filter section, add either Default Billing or Default Shipping