Thank you for this. On the website it states:
Under the e-Toll program, once you pass through an electronic toll, you will pay a convenience fee of $3.95 for each day of the entire rental period, including any days on which e-Toll is not used, up to a maximum of $19.75 per rental month.
You can avoid the convenience fee and any other charges by paying the toll in cash, using your electronic toll device, or avoiding any cashless toll road or passage.
We're flying into Tampa and other than Disney, most of our traveling will be done in that area. Hopefully we won't need a cashless toll road.