Good shape used TerraTrike Sportster 27 speed with an E-bike Kit electric assist.  The Sportster is an aluminum-framed trike that is lighter that its steel-framed cousins.  The 26 inch rear wheel allows it to travel faster with less effort.  The electric assist is an E-Bike Kit 500 watt motor with speed sensor and throttle.  It includes comfort pedals for safety and versa bars to assist entry and exit from the trike.