You donít have the money or means to market yourself the way a mega-corporation does, so itís highly unlikely that youíll have a problem with demand, be unable to meet it, and lose all those customers.
The more likely scenario is that youíll create the product, put it out there, and get a few bites. From those bites, youíll learn what works, and what doesnít, and if you make an error on one personís order, or two peopleís, you can do what the mega-corporations increasingly donít do:
You can write the person individually, explain the situation, apologize, and make it right. [...]