Gibbs Technologies recently introduced an amphibious vehicle called Quadski. This Quadski has four-wheels like a car, but it can be folded / retracted naturally once you’ve entering to the water mode.
Gibbs Technologiesis the World’s only High Speed Amphibian (HSA) technology specialist, and Quadski is their latest amphibious vehicle prototype. Quadski is made by combining Jet Ski and car. The vehicle will be able to move like usual car (max 52 mph) on the land, or it can be speeding up to 72 kph on water surface. Pricing and availability remains unknown. But I’m sure you should pay ten thousands of dollar to get one.