Are you going to have access to a computer and internet while you are here? If so, you can either go to the restuarant website and they usually have their nutritional info online. Or, one of my favorite sizes is Dotti's weight loss zone
www.dwlz.com/restaurants.html (I'm not sure if I'm able to post links yet, so I hope that works). But its a great site with tons of restaurants and their items broken down by calories, fat, etc and many of them by Weight Watcher's points. But it is a great one stop reference place.
One of my favorite restaurants here is Sweet Tomatoes, its a salad bar buffet. But, like all buffets, you can easily go overboard and by saying you are eating salads, you could be fooling yourself, so be careful.
The biggest thing about Florida in the summer is - its HOT! I mean super hot, super humid and super muggy and we've hit the summer weather with daily thunderstorms. Be sure you are drinking plenty of water and stay hydrated. There is enough to do to stay physically active, but remember to take it easy during the heat of the day so you don't get sick from the heat.
Other things to consider - Publix, ALbertsons and Sweet Bay grocery stores have pretty good deli departments that have great premade salads. I'm a Publix fan, they usually have an inhouse sushi bar, salads, deli and in the deli you can get the low sodium boar's head meats (deli meats) for sandwhiches.
QUite often my hubby and I will simply pick up salad and sushi from Publix, head to the beach or park and have dinner there that way. Much cheaper than a restaurant, nicer atmosphere and you have some control over the portions and what you are eating.