Do you know what happens to Amazon and USPS packages that never arrive at your door? While porch pirates may be your first thought, your items could have been misplaced in a warehouse or lost in transit from one delivery truck to another. After several months of going unclaimed, those packages may be auctioned off or sold at local swap meets.

A few TikTok creators have popularized the concept of buying lost packages, posting videos of warehouses full of mystery items waiting to be unboxed. TikTokers have unwrapped gift cards, Nike sneakers, and name-brand purses in addition to cheaper fare such as socks. Before you buy at a Postal Service auction, you can see some of the items on display so you know what you’re getting.

We’ll show you how to buy unclaimed packages from Amazon, the US Postal Service, and other delivery services.

If a US Postal Service package is not claimed within 90 days, it will most likely be auctioned off on GovDeals, a company with whom the US Postal Service has a contract to sell unclaimed items. Items may be sold in lots rather than individually, leaving you with a plethora of items to sort through, resell, or donate. On the website, you can browse categories that interest you, such as sporting equipment, beauty supplies, and clothing.

The website Liquidation allows you to select the company from which you want to buy bulk packages, such as Amazon, Target, Walmart, Lowes, and Home Depot. Some items allow you to see what you’re bidding on, but others only show images of the boxes or pallets and the category it belongs to, as well as an estimated retail price.

Please keep in mind that shipping can cost up to $100 depending on the size and weight of the items you order.

If you want to buy undelivered items, you can look for vendors in your area to see if there is a local swap meet or other places that sell undelivered items. Websites such as Swap Madness can assist you in locating a vendor who may have packages for sale, such as a flea market stall.

Please keep in mind that some days may be better than others for finding packages. For example, a TikToker went to Treasure Hunt in Evansville, Indiana, after it had just been restocked with packages and discovered a plethora of items for sale. A Business Insider reporter went to the same store on a weekday just before it restocked and found everything picked over.

If you’re going to travel several hours to visit one of these stores, we recommend calling ahead to find out when shipments are expected. You run the risk of purchasing items that aren’t valuable to you unless you can see exactly what you’re buying. What you don’t want to do is put your money in the hands of someone who gives you nothing in return.

To ensure the seller’s legitimacy, we recommend visiting the Better Business Bureau website and reading customer reviews. On the BBB website, I discovered a company with reviews from customers who reported not receiving their packages for many months and receiving fake tracking numbers.

We recommend going through sanctioned unclaimed package auctions, such as GovDeals, for legitimate sellers and sources. FedEx has a unique method for handling unclaimed packages. If the package is undeliverable, it will be placed in temporary storage, such as a warehouse, or disposed of “in accordance with local law.”

UPS does not specify what happens to unclaimed packages on its website, but some Reddit users claim the large delivery company sends the items to be auctioned.