Hi rackermike,
The cable modem you currently have would be sufficient because it is a Docsis 3.0 modem. You want to make sure the equipment (wireless devices, network cards, etc.) that you are using in conjunction with your router can also support the speeds. Unless there is a promotion, there is no free equipment but you do not need a modem, the one you have will work with the Gigabit service. So far as specifics on installation fees, you would need to discuss that with our Sales department, but there is a charge for a professional installation.