You may be familiar with Porsche’s Exclusive Manufaktur personalization program, or its Classic setup that provides parts and restoration support to classic Porsche models. Meet the zenith of these two services: Porsche Sonderwunsch. If you’re thinking that sounds like the word “sandwich” in German, rest easy—”sandwich” is the same in German as it is in English. “Sonderwunsch,” on the other hand, translates from German as “special request,” and applied here is shorthand for a new one-off custom car and total refurbishment service being launched to cater to Porsche’s most discerning customers.

Want Porsche to build you a complete one-off sports car? Done; Porsche calls that branch of the program Factory One-Off. Need your classic Porsche brought up to date and freshened? Also done. Feel like combining the engine from a modern 911 with your classic 911? The Sonderwunsch program is all ears. We’re told the only two limitations on what the new program can pull off are that Porsche won’t touch a limited-production model, nor will it copy parts or design from another brand.

Beyond those two no-nos, Porsche Sonderwunsch will hear you out. That part, of course, costs money and is surprisingly involved. Consultations on potential projects can last over one year, we’re told, and include feasibility tests such as whether a chosen interior material works with onboard safety equipment (such as airbags, which punch through special perforations in leather, plastics, and the like) and whether certain engine swaps are physically workable. For these reasons, the exploratory phase for a Sonderwunsch project will cost 100,000 euros, or about $121,500 at current exchange rates.

Naturally, when given the opportunity to interview Porsche employees about the new Factory One-Off program, we peppered them with a number of fantastical, possibly idiotic project ideas, hoping to probe the limits of what is possible from Sonderwunsch.

How about a 718 Boxster convertible converted into a coupe—so, essentially, a 718 Cayman but custom-built? Or what about a Cayman with the roof cut off to make it into a roadster? Could we install an air-cooled 356 engine in a modern Porsche Macan crossover? For the most part, Porsche representatives demurred, stating only that they’d look into things were a customer to ask them and, unlike us, pay them six figures to do so. We were told that a customer approached the company about installing a Porsche airplane engine—yes, Porsche made one, called the Porsche-Flugmotoren—in a car. The company passed on that customer’s, um, interesting concept.

Porsche actually expects most Factory One-Off and classic car refurbishments to be fairly tame—paint color changes, interior material swaps, new trim, that sort of thing, along with perhaps mechanical and chassis modernization and upgrades. Interestingly, the company will not electrify classic or otherwise traditionally gas-powered models—its goal, even with one-off projects is to achieve a factory level of fit, finish, and performance. While such a conversion is possible from an engineering standpoint, the company admits, it wouldn’t live up to the program’s standards.

If you’re balking at the price of merely exploring an ambitious Factory One-Off Porsche or a classic refurb, consider this: Porsche puts customers at the center of their very own development team, staffed with designers, materials experts, and engineers. Being part of the process is a big part of the thrill, but it also means exacting control over your dream. Meetings will be hosted virtually, if the customer desires, and can be kick-started at Porsche Experience Centers here in the U.S. or at the home office in Zuffenhausen, Germany.

Porsche isn’t the only player in the bespoke space. Other luxury automakers, like Aston Martin’s Q division, Bentley’s Mulliner, and Ferrari’s Atelier, have broadly similar customization programs. And given the resources required, Porsche is only taking on three to five Factory One-Off projects each year, along with an equal number of classic refurbishments. If you have the means and a burning desire to do something entirely individual with your Porsche new or old, and want to see if Porsche can make it happen with a factory level of execution, get ready to make a Sonderwunsch.