Appletv4k

Get the last version instead of this one because it’ll save you a pile of money and you’ll still have updates for seven years.

E: if you haven’t ever bought Apple stuff secondhand, they take extreme measures to prevent theft and reselling which takes the form of device lockout. What this means is that someone might be selling a locked out device that can’t be recovered to you. Make sure you actually see that the device goes to the first time setup screen (or have the seller do a reset in front of you) or use a marketplace like eBay that does very easy returns.