One comment on Verizon Unlimited Plan: we use it and it works well but make sure wifi calling is turned off while in the BVI. We left it on, and interestingly, wifi calling is not covered under the Verizon Unlimited plan so we were charged for the calls that were unknowingly routed via wifi calling.
Use WiFi calling for calls outside the BVI and the calls cost nothing. However, using Wifi calling to make a local BVI call routes the call through the US back to the BVI and you are charged the standard rate for a call from the US to the BVI.
