Pulling a Meraki, and the Consulting Move
Hardware startups face a catch-22: factories want big minimums before you've proven demand. The answer is to assemble the first units yourself. Pebble's founders hand-assembled their first watches, then raised $10M on Kickstarter. Bonus: you learn things like 'how valuable it is to source good screws.'
The B2B software equivalent is the consulting move: pick one user, act as if they're your only client, and mold the product until it fits them perfectly, then expand outward. Viaweb literally sold luggage and pens through their own software to learn merchant needs.
One warning: the line is crossed when they pay you by the hour. Then you're a consultancy, and expectations change.
Key idea
Build the first units and serve the first customer by hand. The learning is the point, and it de-risks scaling. Just don't start billing hourly.