We used to use refurbed Thinkpad X220s for all engineers in the business - cheap, widely available, capable enough and with a docking station to use as a deskto

We used to use refurbed Thinkpad X220s for all engineers in the business - cheap, widely available, capable enough and with a docking station to use as a desktop. They'd take 16GB of RAM, though the official spec said the maximum was 8GB. We moved onto L390 Yogas afterwards, which takes up to 32GB of RAM - I've been very happy with mine. Both have been pretty solid for me, though I think the X220 probably had a lot more rough treatment overall.