Twinmotion 2021 “demo” is available for non-commercial use. (it’s not really a demo, and it doesnt expire)
For quality (realistic, non-biased) renders, Indigo makes IndigoRT (a “lite” edition) which is €145 for a perpetual license. It should do what you need (ie,model materials etc within sketchup and just use the renderer for lighting).
A trial would be a good place to start. I’d invest no more than a few days in learning Indigo (or Twinmotion). Most of the tricky stuff is in getting advanced materials looking perfect, atmospherics, motion, etc…it’s a bottomless pit of trial and error!