I have a friend who frequents the government auctions like this one http://www.govliquidation.com/auction/view?auctionId=12168995&convertTo=USD and buys almost anything with metal in it. He especially likes the huge spools of copper wire. They sell for pennies on the dollar and he takes them directly to the smelter here: https://www.cmcrecyclingdfw.com/current-pricing/. They pay him for the metal based upon the type of wire and how easily it can be recovered. According to him they are experts at assessing the quality of the metals in the wire, etc.
He once drove to Oklahoma City to pick up almost a ton of copper wire. He rented a big truck, drove it from the government warehouse to the smelter in OKC, turned in the truck and returned to Dallas the same day. He made more than $450 on the exchange after paying for the wire, truck and gas. They used a fork lift to load it into the truck and the smelter used one to take it out.
He is also a gold reclaimer. Heās bought from an auction thousands of pounds of old electronics and has recovered several troy ounces of gold in the last year. It is a lot of work, but he considers it a hobby. Heās an executive here at my current employer. He is a DMS member, too. Iāve tried to get him to teach a class on it, but heās pretty busy.