I'm making the device now. I'm actually several iterations in but it's shaping up. I think I will be able to launch the Kickstarter in about four months.
I'll probably set the lowest possible number for "success". That would include remaining legal expenses I haven't paid like getting it UL listed, etc.
So say I set the Kickstarter goal to $20,000. I could put $2000 in myself and I think get another $2000-$3000 from local supporters. That's 25% funded which I think has a chance at providing the initial momentum the project will need.
Say I get to this point. I've had a successful $20,000 Kickstarter. I order ~500 boards and cases and assemble and ship them myself.
But then what? I'll have a successful POC and made a net profit of maybe a couple thousand bucks. How do I grow it from there into a bigger product? For example, I think the invention could be useful to a larger percent of the population than I will capture with just Kickstarter marketing.
I think I can do a successful Kickstarter but I don't know how to capitalize on that.