Amazon just put several new and refurbished Roku models on sale. The refurbished Roku Premiere is $48. This is the latest model and is the least expensive 4K player Roku makes. For a little bit more, you can get the refurbished Roku Premiere+ for $65. I think the “plus” model is well worth the extra $17 because it adds HDR support, ethernet, a microSD card slot, and a non-IR remote that does not need line-of-sight to work.
If you don’t like buying refurbished devices, the brand new Roku Premiere+ is $79, which is down from $100. For all the bells and whistles, you can get the Roku Ultra for $117, which is down a bit from the regular price of $130.