Voice Communication Options - Caribbean Area

[SimplerLife]

I haver searched the forums and weba nd feel like I am going in circles. We will be crusing the leeward and windward carribbean islands beginning in April. We have just learned that we need to be able to make phone calls for 1-2 hours per day while a business we are selling is in transition for a year. Spot sat phone looked like a good option since they have an unlimited plan but have heard from a few that their service sucks. Iridium sat looks incredibley expensive for the usage we need. Doesn't look like any cell phone providers will be reliable in all areas.

Any insight/suggestions that can be provided would be helpful. thank you!