Ok, here's an update:

They claim one rental was not removed for a week (but they see me adding the next rental, and I got 2 confirmation of change emails that day.) Obviously no customer would log on, add rental 2, and just leave rental 1 on there that had been returned. They wouldn't refund, but gave me a fax # to send my plea in with the Enterprise contract showing when the car was turned in. Since obviously that new renter did not know I was being charged, he/she paid their own way and technically it was double billed. It's not a huge amount but will try anyway.

For the Platepass - they wre actually very nice and said as long as I can show that there was at least 1 other charge during that rental period on my SunPass, they will refund all of the administrative fees and just charge the normal toll. So that is all settled up. The guy had seen this happen before but couldn't explain how or why or what to do to avoid it. So I guess we are back to Enterprise for now.

SunPass also said the Mini's are never allowed in rentals - I guess it does work (mostly) but since it is stated in the agreement as not allowed, they aren't going to credit any errors coming from that. Sucks, so if we rent a car for a few days to take a road trip, we either have to pay cash every time or buy a portable.