You can stop and pay or just drive through and they will send you a bill in the mail.
There a lot of toll roads in south fl.very few will take cash or credit cards. They are switching to toll by plate. If you have a rental car you have a choice to pay for there sun pass around $13 a day or buy a sun pass at almost any where and have it activated for the rental car. That's the cheapest way to go if you plan on visiting more than once. Other wise pay for the one from the rental car company. Don't go without one.
From everything I've read and been told, and I attempted this once, south of Miami on the Florida Turnpike you must have a SunPass as the tolls no longer accept cash. For FAQ's go to www.sunpass.com
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