There are expensive items that you can purchase for a greatly reduced price, deep in the corners of the dark web. They generally will sell for about .30-.60 cents on the dollar. That sounds like a good deal and the price is right, but they are stolen items. They claim to not be stolen and sold in the same country, so the odds of you getting busted for receiving stolen merchandise might be minimized if they actually do that.
Also, a majority of the stolen items will arrive without the accessories needed to use them. Power cables and other specialized items needed to operate the item you buy will be up to you to obtain. I am unsure why, but even items new and in the box will be missing the accessories. Add to that no warranties, no returns, and concealing or receiving stolen merchandise. It makes the savings in price seem almost insignificant. I would not recommend going this route, most of the time.
These items are not generally available in the main darknet markets. You will need an invite to an “invite-only” market or a link to a private seller’s web page. Be careful. Many of these sites are scams.
When you see a site selling “carded merchandise” that merchandise is still stolen. It is purchased by someone using someone else’s stolen identity and credit cards. It is easier and safer for these “carders” to purchase items online and sell them quickly at discounted prices rather than use the credit info to obtain cash directly. Here is an example. This is the front page of a “carding shop” of this type on the dark web.