There are large error margins on localized effects and time frames. Sea levels will not rise equally everywhere and in many cases local weather like rainfall, s

There are large error margins on localized effects and time frames. Sea levels will not rise equally everywhere and in many cases local weather like rainfall, sea temperatures and air pressure will have a larger effect. Then you've got how those changes effect the local land which may suffer from more or less erosion and could now be at risk of storm surges. You've got to get the timing right too, a property 4 meters above sea level might only be beach front for a decade before another meter of rise swallows it, to invest you'd have to assume someone would buy it at that point. There would likely be enough buildings and trees visible in the water to remind any potential buyer of their short sightedness. Not all waterside property is equal either. There won't be time for a beach to form on your waterfront, so it wont command the sort of values that many do today. Nearby structures out in the water would make for a poor boating and fishing experience and probably give a pretty gloomy ocean view. There is more than enough uncertainty to make it a poor investment, even if the science was 100% certain.