SAN DIEGO ( TheStreet) -- That new-car smell only lasts so long. Luckily, Mitchell and King have come up with something just as satisfying. The Scottish company has just started selling what they're calling the world's most expensive car shampoo. Dubbed "SPA -- Bespoke," Mitchell and King's $375 car shampoo is made to order and delivered in an engraved crystal decanter. Yes, crystal. Because if there's a Ferrari or Bentley in the garage, a plastic bottle of car shampoo would be very out of place -- in fact, John Johnstone, Mitchell and King's owner, says he developed the decanter at the request of a client who did not want a plastic bottle in his garage. "Our products meet the grandeur of the vehicles," Johnstone says. Each fragrance is blended to the client's unique specifications, so no two are alike. Once a particular fragrance is made for a client, Johnstone will not sell it to anyone else. "A lot of people stay safe with their choices and go for scents such as watermelon or pomegranate. Fruit smells are very popular," Johnstone says. "But we can do anything they want. If someone comes to me and says they want a shampoo that smells of leather, I can do that." The first bottle sold a few weeks ago to a client in California who has a sizable collection of cars, Johnstone says, and the majority of orders are from the United States.The shampoo is selling so well it has earned a permanent spot on the company's website. "Like many luxury items, products like this will have a niche market," Johnstone says. The SPA shampoo is one of the cheaper items sold by Mitchell and King, a company that describes itself as "one of the most unique and exclusive car wax artisans in the world." Other items on the site include Emperor car wax in a titanium box for $18,000 and, if money is truly no object, a Gold Rush Rally wax that comes in a 24-karat gold plated canister and gives your car a gold shimmer. The price? A mere $97,443. "Some of our products are more bragging rights," Johnstone says. "Car people as a whole are quite competitive."