Description
Unlike most tents that are only meant for sleeping, CARSULE provides you with a living room in the outdoors and offers mobility since the simple installation makes the movement possible and easy. The cubic shape allows for a 2-meter standing height making the interior a suitable space for a wide range of indoor activities. The CARSULE is designed for cars that have a tailgate that swings up. You are no longer limited by your internal car size. Its expansible space allows for unlimited configuration according to your programmatic needs. Thanks to the hatchback, CARSULE has great reliable support and it can be installed quickly. With the guy rope, CARSULE can even withstand a strong breeze.

Successfully funded on Kickstarter at $17,700

Designed for cars that have a tailgate that swings up
Car door, in its "up" orientation serves as structural support
Diagonal ceiling tension lines prevent shear deformation while doubling as a means to hang accessories from the ceiling
Adaptive seal is designed so that the CARSULE can latch onto a wide variety of car models
6.5ft high headroom space, waterproof & UV resistant for a cozy outdoor cabin
Expansible space allow for unlimited configuration according to your programmatic needs

Specs
Color: black
Materials: polyester fabric
Product dimensions: 78.7"H x 70.9"L x 78.7"W
Pop-up assembly
Integrated mosquito netting
Standing height: 6.5ft (2m)
UV protective coating
Robust waterproof flooring
Ceiling tension ropes
Anchor strap
Adaptive car seal + magnets cord
Easy connect frame joints
Lightweight assembly rods
Screw-in pegs & guy ropes
Thick felt carpet
2-layer multipurpose screen windows
Well-protect floor area
Does NOT ship to PO boxes
Manufacturer's 1-year warranty
Includes

CARSULE
2x ceiling tension ropes
4x guy ropes
4x screw-in pegs
2x magnet cords

https://youtu.be/ZsnzRJwYlrc

Hmmmm ....
They are about $249-$299 HERE ...

This reminds me of the Pontiac Aztek with its factory built-in tent: https://www.motorbiscuit.com/the-pontiac-aztek-is-actually-cool-now/

I completely forgot about that, actually ....
I don't think it's a bad idea, not at all ...
I guess it all depends on exactly what your usage is ...