Is that for 30/4 or 18/3 as OP stated in one post?
They advertise $29.99 HSI here, but if you read the small print fast enough on the commercial, it says must be bundled with at least one other service.
There's a few discrencys between OP's call to Charter and what has also been said here.
Charter DOES vary by area, and apparently, wildly!!--
The Firefox alternative.