The jrFoxyCart module is a shopping cart system for Jamroom. It uses FoxyCart.com's API to handle the integration with the payment processors.
When this module is active in your Jamroom site you will be able to sell items, sell merchandise, sell subscriptions.
It requires the purchase of at least the STANDARD plan which at the time of writing this is $15/month.
Signup for a Free FoxyCart dev account