if you don't go pay before they send you the bill based on your license plate they add a service charge I think 20 dollars
my cousins drove down to TN and had never done tolls before during covid there was no way to pay so just drive on
10 dollars in tolls between down and back 40 in service fee 20 for each day is I think what they said.
vs you pay a 10 dollar deposit on the box or you may even be able to register your plate number to an account and put what you will need for tolls on it that money stays on that account at least for very long time if not indefinitely
yes there is a way to pay by plate I just checked their site
https://www.getipass.com/