Avis - Priceline Pricing for one way with Avis

Kind of at a loss on what is going on. I'm looking at a one way rental on Priceline from MCI to OMA at the end of April. If I book the car to pick up at 11:30pm and return it no earlier than 11pm the following night in Omaha, the price is $20 per day plus tax (total, $35). If I try and return it any sooner, the price balloons to $99. What am i missing here? What if I say i'm going to return it later in the day and return it earlier? Putting in the same thing on Avis' website results in over $150 charge...I would jump all over the $35 one way rental, but just wondering what I am missing. I don't want to assume i'm getting it for $35 and when I show up they decide to tack on the one way fee. Anybody seen this before or relay their past experiences with it? Thank you.

Ah, the old 'one way rental fees change drastically depending on pickup/dropoff time'. I've played this game more than a couple of times - usually an IAD (Dulles) to BWI (Baltimore Washington) rental.
Depending on the time of day I picked up on Sunday, the rate would triple. I always booked for the cheaper price even if I was getting in later. The only time that became an issue was when they changed the rate on my rental prior to me picking it up. I went inside to the counter and they adjusted it back down to the lower rate.
I don't know if I ever played with return times.

My guess is that you're going inside/outside of weekend rental timeframes.

Just book it for the parameters that get you the lowest rate and print out the reservation. I wouldn't worry about an early return but I'd double check the receipt after dropoff to make sure it's the same as what you booked.