Also, I notice you've uploaded some elements onto the project page, just thought it might be helpful to clarify some things with regards to the price-function and pricing graph.
Currently, your price at 10 orders is $313.16, and your price at 50 orders is $291.92. I understand that you might just be experimenting with the figures for now, but I thought I'd just give you an example of how to think of your costs:
- Fixed costs: Costs of concrete mould, business costs, leather costs
- Per-unit costs: Costs of producing each additional unit, in this case the additional concrete used
Your per-unit costs should not be a figure of how much each unit costs to make, instead you should try to split it up into fixed and additional per-unit costs so that your costs don't overlap and the cost savings can be passed on to your customers.