I agree with Richard for two reasons.
One, if you're the founder, you can always sell -- simply by virtue of the fact that you're the founder. Particularly in tech companies, you can be socially inept and you can show up to meetings in flip flops, and you'll still be able to sell.
Like Zuckerberg's business card used to say, I'm (you're) CEO, Bitch!
Second, if you're the lone developer, in my experience, your skills (and your vision) will be better exploited if you promote yourself to product owner and technical lead -- and outsource all the coding (on upwork.com).
You'll end up with faster development and better quality code. Not because your subcontractors can code better than you -- but because, as technical lead, you ultimately have MUCH greater control over quality.
Better still, you'll discover that you can combine the bus-dev roles and the product owner / tech lead ones and find that you end up working fewer hours than you do now.
If YOU can't sell your own product, then you have a product-market fit issue -- and the earlier you recognize that the better.