No, there are no additional costs. The use of the fileeeBox and the fileee app is free of charge.
To use the box, you only need a free fileee account and a mobile device. A premium or professional account is not needed for the use of the box.
In the free version of fileee there is a monthly upload limit for documents - but this does not apply to documents that are scanned using the fileeeBox. So you can upload unlimited documents with your box.