I would also take the LVB option, and while the beach is not a swim beach they often have pools behind the rocks that are nice to relax in. LVB is peaceful. I am not a fan of the beach in front of Flamingo or SBR, and even if you wish to stay there the battle to get chairs with shade is a pain. It is also nice to have two bathrooms and the extra space.
LVB I think is only TS tax, wifi is free and I don't think there are any other charges. Not sure about SBR.
We have actually done the keep two units before, when MJ's parents were coming down and we got a Belair unit besides their Divi unit. With their mobility issues and where they put them at Divi we moved them to Belair and that made life easier for them so it worked well for us.
Enjoy your trip!
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