With a family
of 5 starting out from a firm base but only for one year I would go to the Caribbean
and buy something there and do that area and sell the boat at the end in the same or similar place.
You wont get a Hallberg Rassy
for $100k but you can get a beneteau
For 4 humans and a wannbe you need a 40 footer or more.
if you start in other localities its either too much of a culture shock, or too 'close' to the USA. The Sea of Cortez
would be wonderful but its only one 'other' culture. the Caribbean
has many; the Med most.