No refunds

The Cyber Wagon isn't available in the shop by default; first you need to feed a coupon back into the Awesome Sink to unlock it. Then you can buy the Cyber Wagon in the Awesome Shop, which will cost 20 coupons.

You'll need 10 Reinforced Iron Plates to build it, and then you can get in and drive it for the achievement.

You probably won't want to drive it again afterwards though...