At the time of writing this, the cheapest desktops start at about $130. There are plenty of different ones below $200. The hardware looks decent like 8 GB of ram and SSD disks.
Newegg is one of the most popular online electronics stores in the USA. Their top category is computers, which includes desktops, laptops, gaming computers, and refurbished computers.
You'll find some cheap computers here with desktops starting at $300 and laptops starting at just $99.
The cheapest laptops starting at just $82. In total there are 170 laptops and 140 desktops priced at $500 or less here. Many of these items are discounted.
Walmart is famous for offering a huge selection of products at really low prices. Groceries, clothes, shoes, jewelry, appliances, furniture. You will find mostly anything here.
Target has cheap desktop computers, gaming computers, monitors, laptops, and tablets from several different brands like Apple, HP, Dell, Lenovo, and Acer. Computers start at $109 and go up to $5,060, including discounts up to 15% off the original price.
eBay is an online marketplace where you can sell and buy mostly anything. Both second-hand and brand new products.