SIM for multi-country Europe trip and options for calling home
Apologies for yet another "what SIM?" thread but I haven't seen one that quite fits what I'm looking for. Please merge if need be.
In late March and early April I'll be taking my first trip to Europe spending 19 days spread between London, Lisbon, and Paris with a trip up to Normandy and I'd like to avoid having to go buy a SIM in every country I'll be in. I read in another thread that Three is a popular choice for prepaid SIM in the UK and see they have roaming partners in both Portugal and France. After researching options on their website their £27.50 30 day plan looks perfect for my trip. Am I missing something obvious (or maybe not so) that this wouldn't be an option for me? I'll be using my iPhone 7+ which is on Verizon and is according to them unlocked.
Also I'm wondering what would be the easiest and cheapest way to call home to the US a couple times where there? For friends and family with iPhones I could use face time audio but for others with Android phones I'm not sure what'd be my best option. In the past when I've traveled to Mexico I just used a T-Mobile prepaid SIM which offered calling between the US, Canada and Mexico but obviously something like that doesn't exist for my Europe trip; at least that I know of.
Any advice is appreciated!