I am a Florida native and there is NO WAY you want to be down here even at night without Air con. At night it can be in the 80s and plus the humdity. Ft W is in central Florida so many times you won't even have a breeze and also this is a rainy month. If you can figure out a way to fix an ac in your camper I would say a vacation in Florida in August is fine if you can deal with the heat and enjoy spending time at the pool (please wear sunscreen, lobster campers are hard for us to look at

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Another option might be the value resorts new suites, some of them come with kitchens etc or even check out the FT W cabins. During some months they have pretty good deals. If you are on a budget, what I would recommend is getting a recommendation to a local grocery store I would suggest Publix (quality food and clean-I know some people do walmart also) have a meal plan and go get your groceries there. The cabins have a grill so you could even have a steak dinner. Eating at disney is a huge expense so if you have a cabin or a value suite where you can save on meals that will help your over all budget.