Maybe Digby, certainly are some cheap ones around. However I just recently got my first ever laptop from a police auction. Never worked on one before, came with no hdd, no RAM, missing the hdd caddy & cable, and a faulty keyboard as it turns out.
As long as you are reasonably good at figuring tech stuff out and take some care it's completely doable by us amateurs

This one even has a fingerprint reader I now log in with.
so my example;
Laptop $100
Keyboard $40
hdd $115
RAM $60
Caddy $35 (took 3 attempts and 2 purchases to get the right one - largely my fault but $120 plus from hp so still a win)
I had to find all the drivers and a copy of windows (key was on the laptop), fix the hardware, and install the software.
For $350 all up I get a pretty nice laptop, have some fun and learn some stuff, and it's even good enough for some gaming which you can't do on most sub $1k laptops.
It'll play WoW, Diablo 3, & Skyrim ok at it's native resolution but can't really handle them well on a 1080P external screen.
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