The cost to produce one unit of a custom product is high relative to ordering one unit of an off the shelf product. We have developed a very high level of automation over the last several years but PCB assembly is still an involved process and does require some manual labor.
We have had great success working with GroupGets in order to crowd fund the manufacturing of open source designs so that a lower unit price an be offered. GroupGets allows users to securely join or organize group buys for any existing product and they then securely handle collection, purchasing, and shipping.
Here is an example of a product we've worked with GroupGets on: