Which things that should be retrieved from the business system to the customer portal is of course dependent on what line of business the company has. Generally, everything that has to do with you and the customer's joint business can be retrieved and presented in the customer portal. If you work in projects, customers want to be able to follow the project in the portal. If you deliver goods, the link between orders, deliveries and invoices is something that is increasing clarity and will facilitate the customers' daily work.
Since nothing is impossible to retrieve and show to customers, the starting point should be to give customers the digital service they most demand. Because you would like the customer portal to be visited also between the actual business transactions, in order for you to be top-of-mind for the customer, it is also good to provide access to historical documents and tasks. For example, if you have service history on the customer's equipment or information about completed projects in your business system, it's a gold mine when it comes to being able to serve the customer with information.
Bizzjoiner customer portal can be used in many different industries where the requirements obviously differ between them. One thing that is always common, however, is the customer's interest in invoices and balances. It is also something that is in your interest that it is always clear which invoices are to be paid and that it is easy for the customer to get copies of these.