There are actually maps which show where the water levels will be at each year. My great grandma's house was recently sold for over $1m and only has 70 years before it will be permanently underwater and likely destroyed by 50 years if there is any heavy rainfall.
I wish more wealthy people would lead by example though. Like instead if Obamas bought much smaller place and made it carbon neutral.
Also, I have no idea, but what is the timeline for ocean's rising to make a place like his on beach uninhabitable? I thought it was much less time, like 12 years or so, there are so many predictions out there.
(EDIT: Apparently sale is not finalized)