An unfortunate user on Reddit bought a 1TB Seagate Backup Plus Slim external hard drive, only to find out that they've been scammed. Inside the enclosure was an SD card for storage, with metal blocks attached to a fake weight.
Western Digital makes some of the best storage devices out there, and their external hard drives are no exception. You can get the 6TB My Passport for just $139 and a 5TB Elements HDD for even cheaper at $115—two great discounts for mass storage.
If you want a lot of storage, for a reasonable amount of money, and it doesn't have to be lightning-fast, then there's still a place for older HDD backup drives in your inventory.