Can I change locks, put her stuff in storage, and provide a post office box for her mail?

I am a locksmith in Ohio, you can have the locks changed as long as you own the house, but i dont belive you can put her stuff out , but after you change the locks you can set up a time for her to get her things at your convience, and let the post office know you dont want to recieve her mail any longer, they will hold it till she gives them a forwarding address. but please check Flordia laws.

I beleive you have to legally follow the eviction process in your state, usually with a 30 days written notice, even if she does pay some amount for rent you can still give a notice "for cause" which doesn't require a reason other than you just want her to leave, but check ur states eviction laws. Usually you can get the answer as to how to proceed by just phoning ur county court building an ask the court clerk how an what to do.