I used to use the local enterprise store for one way rentals to Boston airport when I was going to be gone for 2-3 weeks. Over time they have added and added and added fees to the point that a one way, one day rental is over $300. For that price I can take a limo or park for two weeks at Logan.
Their loss of business, I guess. They seem to be only interested in insurance replacement rentals as far as I can tell now.
Another thing to be aware of if and when you can actually get a one-way rental is that they will give you the worst, dirtiest, highest mileage, nastiest car to you as a one way in order to hand over the hot potato to another location. And the people at the receiving end will then. try and charge you for all the damage, dirt, etc. Take lots and lots of photos on your pickup.