I'm using the CalDigit TS4 for my triple monitor setup and it's been rock solid. It drives two 4K displays at 60Hz plus a third 1440p monitor without breaking a sweat. The 18 ports include 3× DisplayPort 1.4, plus Ethernet, SD card reader, and multiple USB ports. It's pricey ($399) but I've tried cheaper alternatives that couldn't reliably power all three screens simultaneously. Power delivery is 98W, enough for most laptops except gaming monsters.

Plugable UD-ULTC4K. https://www.amazon.com/Plugable-Universal-Laptop-Docking-Station-Usb-C-Triple-Monitor/dp/B0779K9DG2?tag=7649-20

Check if your laptop actually supports three external displays before buying anything! Many laptops, especially MacBooks, have hardware limitations. I learned this the hard way after buying an expensive dock. For Windows users with Thunderbolt, the Kensington SD5700T has been solid for my three 1440p monitors. Make sure to update firmware immediately - early versions had some display dropout issues that have since been fixed.

Check if your monitors have daisy-chaining capability first. If they support DisplayPort MST, you might only need a dock with one or two video outputs and can chain the monitors together. Saved me from having to buy a more expensive dock with three separate video ports.