Yeah, so this was also a point of immense confusion when making my setup. I've also asked very similar questions like you, multiple times, but I never got any solid answers on Reddit. This is what worked for me:

I had an Acer Swift 3 (no usb c) - (now I have a Lenovo L7 Slim with USB C), and a macbook.

I bought this: https://www.amazon.com/gp/product/B00O0M46KO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

And it worked perfectly for everything besides gaming.

With that dock, you only have a single connection to both computers. Switching them out requires changing only a single cord. It's fabulous.

The pain point was gaming. For this, I would have to unplug the HDMI for my main monitor out of the hub, and plug it directly into my PC (gaming over USB 3.0 is laggy as fuck). Not a huge deal, but annoying since it was underneath my desk.

I eventually bought a new laptop that has USB-C. So now, I have a USB 3.0 to USB C adapter, and I plug that into my laptops USB C port. For using my mac, I just take the adapter off and use USB 3.0.

There's no lag between either of these. It's fast, clean, and easy.

___________

1. USB 3.0 is enough if you are not gaming. Otherwise, gaming over USB 3.0 on anything other than something like Hearthstone will not be a good experience. Getting a USBC adapter (costs like $5-15 dollars) resolves this completely and lets you still use a USB 3.0 dock.
2. Simple adapter ($5-15 dollars) does the trick. You don't need two cables, you plug the hub cable directly into your PC (concerning the hub I linked above)
3. This doesn't matter if you buy the $5-15 USB C adapter. I've noticed no difference in gaming performance. Anker has good products. I'm using this: https://www.amazon.com/gp/product/B08HZ6PS61/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
4. The hub I've linked has an audio jack. I have my headphones plugged into that and I literally never disconnect them. The only cords going into my PC/Mac are the USB docking cable and the charger. It's very clean and simple.

You would need to use a DisplayLink adapter/dock.

For 3 monitors a Dell D3100 will be your best best at $170: https://www.amazon.com/dp/B00O0M46KO

Almost all the others are $250-$350: https://www.synaptics.com/products/displaylink-graphics/displaylink-products-list?field_displaylink_category_value=universal_docking_stations

USB-C is just a shape, and doesn't mean anything beyond that.

You have to know the standards that it's capable of supporting.

DisplayLink is basically a USB graphics card, as a result it doesn't even need USB-C.

For a mini-PC, people don't typically want all those USB functions, because they don't want a dock the same size as the PC.

Deal link: Amazon

Amazon has Dell D3100 USB 3.0 Ultra HD/4K Triple Display Docking Station for $99.99.

Shipping is free.

Price:

$70.00 lower (41% savings) than the list price of $169.99

Deal history:* 🔥Frontpage Deal at $105.80 with +60 Deal Score and 105 comments. * 🔥Frontpage Deal at $117.20 with +43 Deal Score and 66 comments.

Customer reviews:

★★★★★ / 9,489 global ratings

About this Item:* 2 x USB 2.0 to 4 pin USB Type A, 1 x headphone input and output 3.5 millimeter. System Requirements(OS)-Microsoft Windows XP / 7 / 8 / 8.1 / 10 (32/64 bits) * 3 x super speed USB 3.0 - 9 pin USB type A, 1 x network - RJ-45. Designed for Inspiron 15 7567 Gaming, 5459; Latitude 13 7350, 3350, E5270, E5460, E5470, E5570, E7270, E7470; XPS 13 (9343) * 1 x display/video: DisplayPort output : 20 pin DisplayPort, super speed cable * 2 x display/video: HDMI: 19 pin HDMI type A, 1x HDMI DVI adapter included * Allow for a triple monitor setup, see compatible Dell models in the description

amazon.com/dp/B00O0M46KO

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Deal link: Amazon

Amazon has Dell D3100 USB 3.0 Ultra HD/4K Triple Display Docking Station for $99.99.

Shipping is free.

Price:

$70.00 lower (41% savings) than the list price of $169.99

Deal history:* 🔥Frontpage Deal at $105.80 with +60 Deal Score and 105 comments. * 🔥Frontpage Deal at $117.20 with +43 Deal Score and 66 comments.

Customer reviews:

★★★★★ / 9,489 global ratings

About this Item:* 2 x USB 2.0 to 4 pin USB Type A, 1 x headphone input and output 3.5 millimeter. System Requirements(OS)-Microsoft Windows XP / 7 / 8 / 8.1 / 10 (32/64 bits) * 3 x super speed USB 3.0 - 9 pin USB type A, 1 x network - RJ-45. Designed for Inspiron 15 7567 Gaming, 5459; Latitude 13 7350, 3350, E5270, E5460, E5470, E5570, E7270, E7470; XPS 13 (9343) * 1 x display/video: DisplayPort output : 20 pin DisplayPort, super speed cable * 2 x display/video: HDMI: 19 pin HDMI type A, 1x HDMI DVI adapter included * Allow for a triple monitor setup, see compatible Dell models in the description

amazon.com/dp/B00O0M46KO

Discord Server: Instant deal notifications on our Discord Server!

Category-wise subreddits:

I use this Dell docking station

https://www.amazon.com/gp/aw/d/B00O0M46KO?psc=1&ref=ppx_pop_mob_b_asin_title

Then I use this usb switch go between laptops

https://www.amazon.com/gp/aw/d/B074TYDJK2?psc=1&ref=ppx_pop_mob_b_asin_title