I think we need to work Billing Module something similar as whmcs sales and shopping options ispconfig3 is very good, but lacks auto sales area something like a whmcs or BoxBilling but is itself ispconfig3 I pay 100 euros for it
There is already a billing module available for ispconfig: http://www.ispconfig.org/page/en/addons/billing-module.html An additional shop frontend will be released in q1/2014.
We are working on the frontend but it has not been released yet. You wll find the release on our website ispconfig.org, in our blog, twitter- and facebook channel when it is ready. To stay up to date with ISPConfig releases, please join one of these channels.
News about software releases get published in the Blog at ispconfig.org and in our facebook and twitter accounts.