Will my EU or Italian SIM card provide free roaming in San Marino, or should I use eSIM Scout?

Negative. This is a critical intelligence point. San Marino is not an EU member state. Your 'Roam Like at Home' benefits from an EU SIM (even from Italian carriers like TIM or Vodafone IT) will not apply here. Your home carrier will impose significant international roaming charges. eSIM Scout ensures you avoid these costly surprises with a dedicated, pre-paid data plan, keeping your communication secure and budget-friendly.