The value of used laptops or desktops are questionable.
It depends on the CPU, memory and hard drive. If the laptop has a solid-state drive that is a plus especially if decent size.
Very old machines are not very valuable unless you find someone who likes to tinker or a collector.
I had my old Commodore 64 in the barn attic since the early 80s and you would think it would be worth something. I still had the instruction and programming books, cassette drive and some disk. Nope.
It's a crapshoot if you get anything worth your time spent to prepare for sale. You must remember to scrub the drive, and I don't mean simply deleting all files. The hard drive should be wiped with no less than 3 passes. Check the solid-state drive, was this used exclusively for the operating system? or was personal data stored there as well?
Sale or donate - scrub the drives.
Not wiping the drives could be a security risk in the area of personal identifying information (PII) and therefore identity theft.