I'm a freelancer, a company I'm working with (which has a government as customer) asked me to write an app (web-based and/or system) to allow them archiving documents, and making them downloadable by given users/groups.
I'm planning to make it with APIs, and to make a light web interface and a cross-platform desktop app.
My question is: How much can I sell it? Based on time developing? A very light, free and nude app (same as dropbox), then make them pay for each functionality (users/groups/ssl/resume downloads/desktop app...)? Or make a global price, based on approximate cost, based on I don't know what ?
It's my first closed source project.