Yes, it's nice to have the ocean on your door step, But it costs, you shouldn't necessarily focus on beach front property.

Being very close to the water is not for everyone, it not only costs more to buy beach front property, but it also costs more to upkeep, consider salt water corrosion and weathering.

That being said, there is nothing quite like a dip in the ocean whenever you feel like it. Fortunately St maarten/St Martin boasts 37 marvelous sand beaches that offer easy access, and best of all they're public, so there's no pressing need to actualy own beach front itself.
Instead of concentrating on a beach front location, go for the breeze. Find out which way the wind blows and choose your property accordingly. You want breeze and shade.

The first step is the most important, finding the right broker is key to succesful real estate investment in a remote location. You will find yourself relying not only on your brokers advice as to the purchase itself, but also for much of the subsequent guidance you will need when choosing suppliers and builders etc.