Other Car Rental Programs/Partners (ie. Alamo, Enterprise, Sixt) - One way rental from NJ to Dallas?

I need to do a one-way rental from NJ (just outside NYC) to Dallas. The rates are outrageous! $800 for 3-4 days.

Anyone know of any good codes to waive drop fees or any other good tips?
Is NJ to TX considered a seasonal inventory shift Hertz and the other car companies want to encourage? (Like the $5 a day out of Florida in the spring)

No, there is no seasonal shift between NY and TX. Seasonal shift occurs when regions that have a natural affinity for each other and hence natural traffic between them encounter a temporary difference in weather whereas the population from one can be traced to migrate directly to the other. This happens between NY and FL in large part because many retirees from NY live in FL and visit in the summer when there's no snow up north and the threat of hurricanes further south.

There is also a smaller seasonal shift between NV and AZ to CA, but that is due to the CA emissions laws more than anything else. When an out of state car drops in CA, it can not be rented locally, only one-way out of state. If a CA car is given one-way out of state, the branch incurs a fine. So over the high demand summer months, CA needs more CA-plated cars and needs to dump the out of state cars people are constantly driving in. The $5/day into CA in the spring is intended to get those CA plated cars back. The similar promotion in the fall is intended to get rid of the "unrentable" out of state cars that came in over the summer by sending them all to Vegas or Phoenix.

The problem in your situation is relative difference in demand. The NY area has much higher demand than Dallas. So, one-ways out of NY tend to be very high-priced to discourage it. By contrast, check Dallas to NY and you'll probably see a much lower price.

As for coupons: Hertz has a one-way weekend rental that will take away the "drop charge." In other words, you pay the same lower daily rate as if you had returned the car to the original location. But this coupon has specific requirements and must be on the weekend only.

Thanks for such a thorough explanation. Where do I find this Hertz coupon/offer you speak of?

It's in the Hertz Weekender section of the Special Offers page.