Create a custom widget to to show equipment for sale on web site
You have a widget to allow web site integration for repair booking and tracking, it would be nice to have something to show available refurbished equipment from the Inventory Trade-In's You could use the same interface as the repair booking to allow customer to search everything or filter by device type, manufacture, carrier etc. online purchasing may be wanted by some but for now you could just allow them to send a message just like the booking module does
Jeff Baker commented
WooCommerce integration does just this, sync's your inventory with your online store. Some features left desired... but it does work.