Hi NickZeik,
You can select the default print report for various transactions by navigating to Customers > Invoices and clicking More actions... > Customize Print Templates.... Assuming you haven't customized your portal to display a specific report, this should do the trick.
Hope this helps.
- Justin
Justin Henderiks
Technical Sales Specialist
Method Integration Inc.
Toll Free: 1.888.925.6238
Local and overseas: 416.847.0400
Fax: 416.640.6027
E-mail: j.henderiks@method.me