I have the Andersen Hitch and I do love it. I believe I paid around $350 for it 2-3 years ago. I could no longer lift the heavy traditional weight distribution hitch. I installed the hitch myself so ordering online or directly from the manufacturer (located in Idaho) might be the best deal. The company is a dream to work with. I've called them a few times with questions and they call me right back and walk me through whatever issue I have. If they come out with an improved part for the hitch, you can just call them and they will send you the new improved part at no charge.
The hitch works very different than a traditional WDH so there are a few things you need to know:
1. If you get it, have the brackets for the trailer welded to the A-frame of the trailer. I was towing through Seattle when the brackets slipped and I lost all weight distribution and sway control (oh yeah, there is more to this story). When I got back I found someone to weld the brackets to the frame. I have had stress-free towing since then. I can drive the truck with one hand on the freeway with little to no issue when a semi truck passes me. I have a 28' trailer and have NO sway. None.
1. NEVER use grease with this hitch. Never. Ever. It will not function correctly if you put one ounce of grease anywhere.
There is a ton of information out there on the Andersen. For the trailer you're looking at, I actually don't think you need one. You could get by with a simple friction sway control BUT your van didn't come with a tow package so maybe it does need one. OR the dealer is just trying to make money. I would wait until you find the trailer you want and then determine, based on the weights, whether you need the hitch or not, or if a traditional WDH would be a better match. I towed my Jayco with a Ram pickup that only had a 3500# towing limit. I only used a friction sway control and had no issues.
I am happy to sing the praises of the Andersen all day long. The biggest complaint most people have is that it doesn't transfer enough weight back to the front axle. I can see where that might be a problem if you are towing a trailer at the very limits of the available payload of your tow vehicle. You will run out of payload WAY before you reach your maximum towing capacity. I'm sure the payload in the van is sufficient for anything you are looking at. The Andersen is perfect for my combination.
As far as the pricing of the trailer going up over night, well, I think they jacked up the price for the show so they could offer a "great deal" to some unsuspecting customer. You happened to be looking at the right time to catch that. I liked going to the shows when I was looking for a trailer because there are often multiple dealers with a variety of manufacturers to look at.
Happy to help any way I can.
Laura