As you start your overwater bungalow and villa research, you'll quickly notice that there are dozens of overwater resorts around the entire world. This is great as it grants people from different regions access to a villa that isn't too terribly far away. If you reside somewhere in North America, particularly speaking, the US and Canada, then you'll note that there aren't any overwater resorts along the vast stretches of coastline. However, there is one within the state of Florida. The Disney's Polynesian Villas & Bungalows is located in Orlando and is a solid choice for families who plan on visiting the area and parks.
If you're looking for a true over the water experience, then you'll want to venture to the South Pacific, the Caribbean, or the Caribbean coast of Central America.
Looking for over water rentals for around 300.00 a night
Candace,
Our other site has an updated list of the cheapest overwater bungalow resorts in the world. The ones in your price category are mostly in Asia. Unfortunately there are none around $300 near Tahiti or Mexico. -Roger