Question Best Cell Phone Set Up for Study Abroad in Turin?

Hello all, I have a son who will be doing a 6-month study abroad stint in Turin starting soon, and I'm trying to figure out the best cell phone set up for him. We're based in the U.S., and I'm wondering if it's better to get an international plan, buy a local SIM card, or if there's another option I'm not thinking of. Also, any tips on reliable carriers in Italy or how to avoid roaming charges would be super helpful. If anyone has gone through this or has advice, I'd really appreciate your input!