It sounds like a good time to raise a bit of money. Don't go crazy, but try to get enough of an investment that one or both of you can start working full time on the company. Or, if neither of you are comfortable with sales, try to bring on a third person who is. Congrats and good luck!!
Thank you! Interestingly enough, our first customer also offered to invest in us six months ago. We punted at first, but a few weeks ago they brought it up again unprompted, so I think they are serious. I’m just hesitant because I’m not sure how it would work to have a customer also be a shareholder. What are your thoughts?
More than that, what goal are you achieving by letting them invest? Will you use that money to hire a full time sales person, or another dev to accelerate the product, or...? Because if you don't know what you'd do with that money, you don't want that money (nor the extra voice and trouble it would bring).
You can always keep this thing bootstrapped. If you reach a point you need an extra pair of hands, you can evaluate if it makes sense to hire someone, and if debt or equity financing is necessary. But if you're not at that point, there's no reason to take that on.
A key thing to remember is being invested in is a means to an end. Ultimately it requires giving up a level of control, or taking on a level of debt; it's not simply 'a good thing to do'.
So even without considering the downsides of a customer as a shareholder, you may want to avoid doing it just because you don't know how the money will advance your goals.
I'd be wary of going with a customer/inventor, you might end up building a solution too tailored for them that you can't resell easily; and there are conflicts of interest for them.
Given the growth you're having organically on just two people and not that much time, I'd try to keep on your own a little bit more rather than searching for investors. That will take time, and hiring more people will also take even more time. Maybe it's worth it to put that time into getting new clients, knowing the market (i.e., what's your upper limit, what companies you can't reach, etc) and maybe growing revenue so when you do take investors and hire more people you're closer to breaking even.
