re: My Dad has Decided to Retire Abroad... Narrowing Down Beach Places

One of my kids spent a year on Ambergris.

(work/study)

I was and would be very comfortable with having a relative there who is in reasonable health & mental faculty.

Nice place to visit too for you.

Any where in the Dominican Republic?

Not so much.

Infrastructure there is patently Third World if/when something extraordinary happens.

Much less desirable to be in than Ambergris, for example in those instances.

Good luck to him.