Look for ex-government or ex-corporate laptops. These are often in good condition, commonly are thinkpads, get replaced every few years on a schedule rather than because of any actual problem with the laptops and often were plugged in to power for most of their operating life so the batteries can be good for the age.

Also look out for clearing house auctions of laptops from bankrupt businesses.

When buying second hand though I recommend that you price in a replacement SSD as they often are at end of life.