We made a makeshift movie theater in a Daihatsu Atrai and went car camping while screening movies.
I used some leftover quilting batting for the screen, but the image quality was rough, so I don't recommend it.
I also bought some popcorn for the first time, but it produces a lot of smoke, so I think it's best not to make it in the car.
[List of tools used]
https://www.amazon.co.jp/shop/dentan
The Amazon link uses an associate link.