I constantly check out dell refurbished for deals on workstations. Pretty good Linux compatibility in my experience, workstation hardware, and they have 50% deals all the dang time. The precision line of workstations looks like it would meet your needs.

As someone who frequents the laptop market, I’ll throw in my two-cents.

If you’re looking for value, don’t compromise on performance, buy refurbished.

While I’m certain it is definitely different from country to country, a refurbished laptop typically has more life to give in them.

I’d recommend business laptops, such as the Dell Latitudes or the Lenovo Thinkpads, but an M1 MacBook Air provides an absolutely shocking amount of performance for the price.

Checking sites like eBay or the pages of hardware resellers rather than big box stores is definitely where I’d go.

My two cents; if you want to use Linux on it, then do yourself a favor and pick a laptop from a Linux-first vendor. So the likes of NovaCustom, Star Labs, System76, Tuxedo and others found on the link over here come to mind. Besides that, it’s important that the device in question either has a dedicated GPU (or at least supports eGPUs). Furthermore, choose a device with relatively high battery capacity; they go up to ~99 Wh, so pick something that’s at least relatively close to that number.