If you use a US based website, most of them let you cancel a ticket with full refund within 24 hours of purchase. Print off your itinerary, and there's your proof of onward travel.
I booked AXA on their website and had a customer service disaster trying to deal with them. But, I'll admit that my story seems to be an exception and that
The Moderna is a better choice than either of the vaccines which the government plans to use. Astra Zeneca is a little wonky, and the Chinese have admitted that some of their vaccines aren't all that effective. If you can afford the private option, it's probably worth it.
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