Just a quick update. I recently added the ability to select quantities for purchasing parts.

I chose to provide a multiplier and an additional field for added percentage. This way you can easily get the right amount of components if you want to build multiples and also account for wastage. The numbers are always rounded up so the default, which is currently at "x 1 + 10%" will likely give you at least two of all the components required. Is this a sensible default or should it just be "x 1"?