The guys from 502 are amazing -- really knowledgeable, very kind and extremely helpful. I know them well and have interacted with them (last a Monterey two years ago).
The price of under $100,000 seems to be for a body and chassis (from their website). I'd imagine that, once it is painted and fully assembled, it would be in the $200-250k range.
The most elusive aspect of the Spyder is the rear fenders. It is a tough shape to get right. Even with the variations between bucks within the Wendler plant, many of the replicas are still a bit different.
The best I've seen is the one from Rusty Tubs.