SilverStar17
Super Freak
You'd be surprised what people will pay for custom stuff, even more so with 1/4 statues where a custom head can cost as much as a mass production statue. There's a market for just about anything really.
Speaking of, who sells the $100 kryptonite spear? I've only seen the $35 one.
Oh no, I'm sure there is. However, I also think it depends on what the item is. Custom capes for instance that greatly improve a figure where the general consensus is that the stock cape is a monstrosity, I think a lot of people will still be interested because it greatly improves the overall look of the figure. Accessories or sculpts that really aren't necessary to make the figure look good because the figure already looks good as is or the stock sculpt isn't a monstrosity, I think there won't necessarily be a high market for.
In order to stay ahead of the curve, the idea is to offer something similar at a lower price or offer something better at the same price or only slightly higher. Even though many customs by private customizers are spectacular, I sometimes don't think they're THAT spectacular to warrant say a $50-$100 price disparity when the mass produced one isn't necessarily that much worse than the custom one. That being the case, I think many people would find it more practical and more price friendly while not necessarily being far worse in quality.
Though when it comes down to it, it's others' money and they're of course by all means free to spend it how they like.
And as mentioned, regarding the spear, Tony Mei's I've heard is in the $100 range.