Nobody has yet mentioned an increasingly important consideration when it comes to beachfront properties--will the property still be there in 15-20-30 years' time? It is becoming increasingly apparent that many beachfront properties in the U.S., especially in Florida and Louisiana, won't be. No, they won't be submerged like Atlantis, but even eight inches or so of sea level rise--and some places are looking at as much as a foot and a half within the next two decades--can make some properties so flood-prone at every high tide and moderate storm as to be effectively untenable, unless there's work done to jack up the whole house and flood-proof all necessary roads and utilities.
Many Florida beachfront communities worry that within a few more years the dawning realization that these properties are no longer good long-term investments will become so widespread that it will torpedo the property values that support most of their tax bases, just as they're really going to need more money to raise roads, build sea walls, etc. to adapt.