Everything is selling slow right now, especially hobby stuff. I have a few other interests, and prices are down quite a bit with that stuff too.
But the only way to know what it's worth is what someone will pay for it. I'd never pay more for a built bike than the parts cost to duplicate it, regardless of the labor involved. However, some might just want a "turn-key" deal.
Something like this is very unique and 0ne-of-a-kind. If you find the right person, it will sell immediately. Otherwise, you might have to discount it severely to sell.