Our finance controller asked for one report that lists every customer account, including the ones we have never invoiced in 2026.
No standard report type can do that with our custom Invoice object, so I built a custom report type on Accounts with Invoices as the related object. I built it in a Developer Edition org with the new Lightning report type editor.
By the end you will know how to create a custom report type in Salesforce, choose between “must have” and “may or may not have” relationships, add fields through lookups, and prove the result in a real report.