Adding a core charge to certain products

Is it possible to add a “Core” charge to certain products that we sell thru woocommerce, what I mean is we sell auto parts and some require our customers to send there used parts back (or cores) and then they get credited back,does anyone have an idea or use the cores in shipping there products if so how do you do it

Example:
Transmission Torque Converter $100.00
Core Charge $50.00

Total: 150.00

But when they return the old convertor they get the $50.00 back

http://wordpress.org/extend/plugins/woocommerce/