GC Policy has changed over the years, and they also have a single policy covering any and all special orders. As of right now, special orders are Cash In Full, up front.
This is entirely up to GC, and isn't exclusive to ESP or anything, it's anything special you order at a store.
I have a local dealer working on a custom quote for me, and I get the feeling they're willing to work with me on the money. Of course it might depend on how crazy the guitar is. If it's a pink Hello Kitty guitar with a Bigsby, they may want 100% cash up front, no matter who they are. Not the kind of guitar I'd want to get stuck with in my store.