The short answer is No Problem. In FL, in a car, a handgun must be "securely encased" which basically means anywhere so that you have to do something to get your hands on it. In a snapped snap holster (which is not on your body), a glovebox or a zippered bag is fine. It can be loaded and the contianer does not need to be locked. The part of the law that says this uses the term "private conveyance", so I think it would apply to a private plane too. You should be fine at parents' or friends' house too. Carrying it around on you in a public place (concealed) is illegal without a permit, unless you are going fishing, camping, hunting, or target shooting. Open carry is illegal unless you are doing one of the aformentioned activities. Non-resident carry permits are avaliable, but it's enough trouble that it isn't worth it unless you are going to be a regular visitor.