Jadnashua
Retired Defense Industry Engineer xxx
What size supply you can live with will depend somewhat on how you use it...if you open all of the valves, then your flow would try to be the sum of all devices, and 1/2" is unlikely to provide you with enough flow to provide satisfactory outputs of any of them. If you want the ability to run all at the same time with decent functional pressure, I think you need 3/4" feeding things, and that's not pex, that's copper.