Looking to buy. Any recommendations (post-2017)

[JordanLantern]

I'm looking to get a ThinkPad for office and some lab work (I do a lot of simulations) for which I need a fairly powerful CPU and plenty of RAM (so the older ones won't work). A new one like the L490 is ridiculously expensive, can anyone please recommend a good one to get used?

[TheForgottenKing]

T480 can be found for $500 if you search well. i5 CPU, 8-16GB RAM, 1080p display (upgrade if necessary), and an ssd. It has a quad-core CPU. Avoid older models like the T470 due to the dual core.

[wujstefan]

Are you simulating using CUDA?

If that is so, P50 would be a friend of yours. I bought mine for $600 with 32Gb of DDR-4 (still 2 slots left), nVMe SSD, i7 quadcore 6-gen and a nicey nVidia quadro for simulation and CAD tasks.

[FryPpy]

...so the older ones won't work...

May be it is right to invest in newer thing... But first that came to my mind in terms Quad Core and 14" is... T440p. Not all T440p is quadcores! It can eat up to 16Gb ram. But clunkpad is here;(
Or may be other T4x0p series. Eg T460p can eat 32Gb ram.
You can think about it.

[TPFanatic]

Second looking for T480 or similar contemporary model, such as L480. Look for one with an 8th generation processor, that will be a quad core whereas 7th gens are dual cores.