The middle class buy suits off-the-rack. The wealthy have tailors create custom garments. It was the same with car purchases, a century ago; the masses bought Model T's, whereas the rich purchased a "rolling chassis" (including the engine and mechanical underpinnings) from an auto manufacturer, then hired a coachbuilder to drop a custom body and interior atop it.
To give you a visual example: Everything metal in the photo below came from the carmaker. Everything you see in wood would have been created (and eventually finished) by the coachbuilder.
The coachbuilder would also add the body. The finished product would look something like this:
A custom 1930 Bentley. Image: El Caganer / Craig Howell - Flickr, CC BY 2.0
As mass-produced cars improved, coachbuilders became largely obsolete. Design consultancy Seymourpowell, however, foresees a return to this type of system, brought about by the rise of electric vehicle platforms. As we saw with Israeli startup REE, one manufacturer can produce an EV "skateboard" that another manufacturer can drop a body on top of, providing an opportunity for designers.
"The rebirth of coachbuilding in a modern age," says Seymourpowell Transport Designer Jonny Culkin, "will allow customers to own vehicles that express their individual identity, values and desires across all vehicle touchpoints." To illustrate the point, they designed this Lean concept. The idea is that they might start with something like this…
…and arrive at this:
"Mirroring the mass platform-sharing used by some of the biggest car groups such as Volkswagen and Stellantis, Lean cars are underpinned by an electric skateboard chassis, upon which different interior layouts and body shells can be applied and 3D-printed with no delay to manufacturing time. Batteries can be moved around to mimic front or mid-engined layouts, whilst crash testing can be done virtually and suspension setups by algorithm."
It's a sharp-looking example for sure. What Seymourpowell doesn't mention is whether this new era of coachbuilding will again be the domain of only the wealthy, although Seymourpowell Head of Transport Design Jeremy White does say "We're digitising and democratising both the build process and ideas around car ownership more broadly, thinking about how people will interact with driving in the future."