I buy 2-4 year old Dell (or similar) micro desktops just for this reason. Just enough upgradability (SSD/RAM, sometimes even CPU) and just enough power but runs cool and quiet.

Recently bought a lot of 10 Dell Optiplex Micros for around $1,200 USD all ready to go (9th gen / 16GB DDR4 / 512GB SSD, Win10 Pro) for a small business that works on spreadsheets and basic data entry all day. Replaced old desktop towers and employees were happy to have more free desk/working space.