Is there like an Optiplex or some similar system that I can buy for under 100 dollars, and then upgrade it and make a profit?
Tip for doing stuff like that: government and corporate auctions. You'll want to buy systems in bulk, at probably less than $25 each. Make sure you get them with OEM tags on them, you'll want to use the OEM Windows key. Stick with Windows 7 era and newer computers. A friend of mine does this, makes $50-75 each, sells them for $100 on Facebook.
