Video playout software and hardware requirements for simple TV channel
Cheapest solution: OBS for broadcasting, mplayer for video playback, someone who will programm simple schedule for $100. If you don't need exact schedule programming, you can just make playlists playback for free! Here no instruction how to setup it for your needs, but if you is advanced user, you can do everything youself.

If you need advert breaks, logo overlays and so on, it can be programmed with infrastructure of OBS, but you can reach limits very fast. You can try to hire freelancers who will maintain your infrastructure and wishes.

Main price for "out of box" solutions comes from any guarantees what will be provided to you. Cheap infrastructure guarantees nothing.