I only have bought one TV in my life. That is the small flat screen that I bring with me to meet-ups to connect to my microscope. Other than that, every TV that I have had has been acquired curbside.
I realized a long time ago that any TV that you find at the curb within a couple days of Christmas is a TV that works but got upgraded!
I never had heard of a 4k TV until now. I suspect it will be a while till I find one at the curb...