Does anyone know of any invoice software solution that allows for customization (or is open source)? I'm finding out for someone I know, they currently work with Quickbooks Invoice Manager 2009. It allows them to customize invoices graphically.
THEY DO NOT need a full-fledged program that Quickbooks is usually associated with. They're simply interested in the invoicing/estimate aspect. Is there anything out there that can fit their needs on Linux (paid or free)? They don't mind if they have to code a bit.
Also, they would rather stay away from web solutions
Any help greatly appreciated.