Held my breath...
Did a quick RT from DCA to BOS. Rented from Alamo, paid them $3.50 or so for each of the 2 days for their "magic box".
I had a pad and pen next to me, thinking I would write down the tolls I passed through, so I could match up whatever I would receive from Alamo. I really dreaded what I perceived to be the inevitable upon my return...
First few tolls, not a problem, signs were clearly displayed, I entered them on my pad. Feeling pretty smart. Went downhill from there, I had no clue as I passed through various toll lanes from DCA to BOS and back, what the heck I was being charged.
Within days an additional charge hit my credit card. Of course I rec'd no itemization, just the charge on my card. It was about what friends told me it would be, $100 or so.
So guess I let out a sigh of relief.
But one crazy way to run a highway system...