Car rental and Everglades tour on our own

[mikaula]

I haven’t been to Miami in 8 or 9 years and my memory is foggy. Im wondering

 if anyone has rented a car at MIA and drove around for several hours and the returned it later the same day?  I have a late flight and the tours thru the cruise line get you to the airport so you cane board by 3:00. Our flight leaves at 9 pm. 

[FOPMan]

Not an unusual activity at all. 
 

There would be plenty of time to go to the Shark Valley area or Everglades Holiday Park and go out on an airboat.