50% deposit on base price?

I’m a Ukulele player and I was looking for a new instrument. On a dealers website I came across an option twhich says “deposit on base price”. When I check that option the total price goes down by 950$, which is 50% of the base price. Since Iam not a native english speaker, I’m a bit confused now. Do they mean deposit as verb or noun? For me it wouldn’t make any sense, to give you the option to get your instrument cheaper or not. You could easily miss that and pay 950$ more.
Here is the link: http://www.theukulelesite.com/koolau-t100-custom-options-upgrades.html
I hope that someone could explain me what the deal with that is, since I didn’t get any response from their support yet.