ECommerce Help/ Administrative Controls

Working on an E-commerce site for internal ordering. Wondering if site can be set up without payment option? Also looking for a plugin and/or features which give administrators more “parental control” such as individual logins for every customer to streamline inventory tracking. And on the subject of inventory tracking, has anyone found a plugin/feature to notify admins when inventory hits a certain amount?
Any help appreciated!


Here is my site Read-Only: LINK
(how to share your site Read-Only link)