Kiawah is on treated municipal water, so filtration here is about taste and protecting equipment rather than solving a supply problem.
Living by the sea does not affect your tap water
Worth saying plainly. The supply is municipal and treated, and salt in the air has nothing to do with what comes out of your taps.
Protecting the equipment you already own
This is the real argument here. Tankless heaters, recirculating systems, filtered refrigerators, ice makers and good tapware are all more sensitive to sediment and scale than a basic tank and a builder-grade faucet. In a house full of that equipment, filtration is protecting an investment rather than improving the water.
Standing water in an empty house
Water sitting in pipes for weeks tastes flat when you first arrive. That is normal and clears after running the taps. It is not a filtration problem, and we would rather tell you that than sell you a system for it.
Test before buying anything
Anyone recommending a large system for a Kiawah address without testing your water is working from a price list rather than from your house.