What things should I keep in mind when buying a second hand Nintendo Switch?
A factory wipe will remove all downloaded games, as will the current owner registering a new system. You do not own the licenses to any downloads, and they can be deleted by Nintendo or the current owner at any time. Furthermore, it would be illegal to access the current owner's EShop account. You should also be aware that even lightly used joycons may need to be sent in to Nintendo for maintenance- this is free, but will take at least several days.