Invoicing personnalized

To make customized Invoices to bill clients for incoming calls through our PBX and Credit Notes for telephone agents. We use spreadsheets with background images to make templates. These background images are supplied by us and allow every client to have his own, personal templates. The spreadsheets with background images, including all 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) 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.: Our Multi-disk Server and Asterisk PBX 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 and quick communications are essential ! This is a Linux only project --- No Windows ! -------------------- Please read and understand the attachment, or ask questions !