DaVinci Resolve 14 Beta 6 is free for now. Paid Studio version ($299 when finalized.) will offer more features. Plus they offer 3 editing bays and four audio bays if you need them (aka Hollywood) but not cheap extras! Windows or Mac.
Also bear in mind that it's very resource intensive (processor type/speed, memory, Graphics Processor) working with 4k files. So a relatively newish PC or Laptop will be required to render in reasonable times.