We have been looking out for a neat Invoicing plugin for quite some time and found various reviews about the different plugin available out there.
We were looking for something rather straightforward, manage clients, manage invoices, manage payments. We initially set out to test the WP-Invoice plugin, however, we soon run into difficultities with some strange error which we found was quite recurrent among various users on the support forum. In a parallel we also found Shaken’s Invoice Lite theme, a GPL distributed free theme which converts a site into an Invoice management tool. A pro version of the theme also exists which allows you to do more customisation and functionality.
The theme does exactly what we need, however, being an Indian based company we needed a little bit functionality, namely the ability to configure Domestic and International clients. We need to be able to configure the Currencies, Tax and payment gateway for each set type of client. We have released our modifications under the same GPL license, and you can download the modified Shaken theme from our GitHub repository below.