Nearly all laptops will supported dual displays with a dock. That is, either 2 monitors (laptop is shut), or laptop + 1 monitor.

if you select any laptop with only one display port toy can use it with four (4) TV.

@Ryan is right. The only factor is a higher end graphics card will support a larger external monitor at higher resolution. Other than that, all laptops have either VGA, HDMI/Display port for external connections albeit a monitor, tv  or projector. Your standard graphics cards should support pretty high resolution so unless you are doing a large TV or large monitor any laptop/dock combo should be more than fine.

With this device and only one Displayport on your laptop you can displays the same Image on 4 HDMI monitors with at least 1920x1080 quality.
https://www.amazon.com/Tripp-Lite-DisplayPort-Transport-B156-004-HD-V2/dp/B01HIOY8VW/ref=pd_lpo_23_tr_t_3?_encoding=UTF8&psc=1&refRID=8WJAFNT3V4VBEWT3H0QP

Typically only Dell Latitude laptops support docking stations (assuming you're sticking with Dell).  But using UBS adapters and existing ports, most if not all laptops can support Dual (or even TRIPLE) displays when you factor in the built-in screen.

But if this is a call center, that seems like a very expensive way to go... why not use thin clients and a remote desktop server (terminal server?)

Just adding to Ramin's answer. The device he recommends can also extend the desktop across all four

Hello Thanks for all of the advice.
In answer to the questions "why not thin clients?" It is because we are in Africa and it means the call centre operators can take their laptop home at the end of their shift and more importantly when the power surges or cuts we only have to have a decent UPS on the switch gear and Vsat. Also we are not wanting a single point of failure. I am also not intending purchasing new laptops either, so a bunch of used lattitudes and port replicators is a very cost effective way to equip the call centre. I have lattitudes here and could never get them to work with both monitors... NOW thanks to you guys I realise that I needed to close the screen for the second mmonitor to work (Duh!)  So will get on testing and get back to you.
Again thanks for all the input, and also the heads up on the Tripp Lite 4-Port DisplayPort to HDMI Multi Stream Transport Hub.

I am new to the EE new interface. How do I give you all points do I just press the assisted solution button?

Glad we could help.

Yes, you select assist for these. Please skip mine because I was just commenting on Ramin's answer

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