I would only be interested in plastic caging for arboreal/semi-aquatic species, as plastic is really good at retaining humidity. For other applications, I almost always prefer wood.
Pricing would depend on what features are provided, for example, molded recesses for lighting and heating, stackability (without needing to buy rack supports), rounded edges, etc. How much I would be willing to pay would also depend on its looks.
Hope this helps, and all the best in your business plan.