Worth noting for ecgz88 that it's pretty hard to avoid tolls in the northeast. In addition to all (or nearly all) Hudson River Crossings, there's also few or no ways across the Delaware River/Bay or the major waterways in Maryland (Chesapeake Bay, Baltimore Harbor, Susquehanna River) without a toll in at least one direction. And of course, you'll encounter at a minimum the longer toll roads (like the NJ Turnpike) as well. And the number of toll facilities accepting cash is decreasing (while slightly outside this forum, worth noting that all tolls in Massachusetts are also cashless (I-90/MassPike and Boston Harbor tunnels/bridge). You cannot really drive your way around tolls here, and might not always be able to pay cash.

That said, I'd say you're unlikely to spend $100 in tolls, which is what the Dollar plan comes to at $8.49/day for 12 days, but $30-50 is quite likely depending on where you go (NYC area being highest), and how much back and forth you do across toll roads (i.e., crossing the Hudson can hit $8-15 each time eastbound, depending on where you do it).