If the lower section of the building is insulated and air-sealed using closed-cell, medium density spray foam like SES NexSeal, the walls could be opened, dried and the sheetrock repaired in short order at a relatively low repair cost.
Back in the day when the global population was half of what it is today, we built on high ground and water naturally flowed down and away from homes. Homes were dry and most were more than 5’ away from each other! Climate conditions have changed, and we are reminded of it weekly, if not daily; 120°F in the Pacific Northwest or back-to-back snow years in Austin, TX. Just as the climate has changed, buildable land options have changed as well. There aren’t many buildable lots on a hill left. The affordable lots are at the bottom of the hill in the crosshairs of the next flood or rain event.
The high velocity winds of hurricanes make dramatic news stories, and the winds can do considerable damage, but more destruction caused by hurricanes is from ground saturation and flooding, not wind. Spray foam provides solutions for coastal climates that regularly face high winds and storm surge. Medium density spray foam is hydrophobic and protects against the flood and rain events as well the wind. Build as high as you can! Use piers when needed and use stem wall slabs to elevate the slab to a safer level above grade for reasonable protection from expected rain and flood events. When the waters do rise, medium-density foam will survive and help to save the rest of the structure.