This year's FL driveout to the Northeast has ended. (Avis still has theirs, but only to the Piedmont region of the south.) You are now doing this out of season (and on short notice), so the regular (high) one-way rates are likely to apply.

The National rate mentioned above from a neighborhood store in Miami is the best retail rate I see. If you haven't yet joined National's Emerald Club, for free, I recommend doing so. Economy and compact are the same price. Using the upgrade coupon on National's website, click on compact, and you can get a midsize for $68/day plus tax.

This thread probably is better off in the Other forum, since it's not specific to Hertz.