I've looked into this before too and their idea of the resin mix (and correct me if I'm wrong and they have changed the formula) but it ends up being more like a low grade pottery mix... kinda bony & brittle and not the plastic like results the resin that we're used to.
And ausf is right... resin mix IS expensive and even more so in small quantities! You're just better off buying other peoples work or metal cans and even kits to glue together. OR, you create a small business and sell the extra pieces to offset the investment.
Just my opinion on it.