Attaching documents
We suggest that instead of attaching documents, you explain the contents of the invoice in the accompanying text. If attachments to the invoice are mandatory, they should be in PDF format and as small as possible. You can achieve this by creating them directly by exporting from a text editor (Word, LibreOffice) or scanning in black and white, maximum 300 dpi. Size is important for storage reasons, in case of oversized attachments, additional costs will be incurred, as a 1 MB attachment is equivalent to 120 invoices without attachments.