DIY in-car Entertainment Package for $300

We take a look at how to add an in-car infotainment system without spending all your money.
We will show the installation process and the final result by starting with planning and drawing the scheme.
As an example of a car, we have a Highlander 2021 with a 1500W power inverter.

The setup could have two monitors as well, the only difference in the setup will be a different HDMI splitter (3 in 2 out), an additional monitor, and different monitor mounts. It will add $150-$180 to the total price.

Prices of the equipment could vary. Most of the items were bought during Black Friday.
Links to the equipment used in the setup:
Monitor - UPERFECT QLED 15.6: https://www.amazon.com/Portable-Monit...
Monitor mount: https://www.aliexpress.us/item/325680...
Streaming Stick - Roku Streaming Stick 4k - https://www.bestbuy.com/site/streamin...
Gaming console - Nintendo Switch: https://www.nintendo.com/store/produc...
HDMI Splitter - UGREEN 3 in 1 out: https://www.amazon.com/dp/B00MWRZFP4?...
Battery backup (UPS) - Cyber power 450VA: https://www.bestbuy.com/site/cyberpow...
Nintendo Switch power adapter: https://www.amazon.com/dp/B09Z653FZZ?...
Power strip - Mifaso 10ft: https://www.amazon.com/dp/B0B2WD2GLV?...
Headphones - Sony ZX110: https://www.amazon.com/dp/B011TNK6V4?...
Dual Headphones splitter - Cubilux: https://www.amazon.com/dp/B0BJZ4BQ1W?...
Cable ties: https://www.aliexpress.us/item/325680...