Invoices and Bills

To make customized Invoices to bill clients, for incoming calls and Credit Notes for telephone agents. We make the background images for the spreadsheets internally. These background images allow every client to have his own, personal templates. The spreadsheets with background images, including calculations, must be changed to pdf without loosing anything, before they are stored on our server. Than they can be filled out on the Internet by our clients and send by email to their final destination, as invoices or Credit Notes. The client never sees the spreadsheet, he only sees the background image and his entries into the fillable fields ! Requirements: 1) Linux Spreadsheets, with interchangeable background images of Invoices and Credit Notes. 2) Software (open source or homemade) to change the spreadsheet files to pdf, without loosing calculations ! 3) Software to connect Asterisk ( CEL - not CRM !) to fillable fields on spreadsheet. N.B.: Multi-disk Server and Asterisk are on different networks ! This is not a standard project and not for beginners ! Very good knowledge of the way Billing software, spreadsheets and Asterisk PBX work is needed. Also Multi Disk Server with KVM disk management and MySQL DB. Good communications are also necessary ! This is a Linux only project --- No Windows ! -------------------- Please read and understand the attachment, or ask questions !