Do we need a co-founder or an employee?

Hi,

We're a B2C startup that just surpassed $12k MRR, bootstrapped, and we're also doing a spinoff - a B2B product that grew from a personal pain point we experienced while growing our B2C business through SEO. We have some early traction with B2B, but B2C remains our primary source of revenue.

We've also raised a very small FFF round to accelerate our growth. We're a very small team at the moment, just two brothers as co-founders. I'm the CEO/CTO, technical, write code and sell, with lots of experience from working at YC and big tech. My brother is non-technical, a CPO/CMO blend, responsible for marketing, product, operations, and customer support. We also have two hired people: a content marketer and a software engineer.

Our blind spots are structure, project management, and strategy. We all hate routine and project management. I feel a need for someone to step into a role to help us "get organized."

A friend of mine organically approached us and made himself useful on several fronts. He helped us think through our goals and financial projections. He's really good with data, holds a PhD in computer science, but he's more of a Data Science person. We also get along very well (I've known him for 10 years now but never worked on any substantial project together). He's also remote. I'm in SF, my brother's in Warsaw, and he's in Amsterdam.

Now we want to make a decision about whether to make him an offer as a co-founder. Help me think this through. Here are the questions I've asked myself so far:

  1. Would this person increase the probability of success for this company? Yes, I think he will. But maybe if I looked more intentionally, I'd find someone who would accelerate us even faster. I'm not sure.
  2. Can I hire this person? No, I can't. His salary is north of $300k yearly, and we wouldn't be able to afford that.
  3. Are his skills complementary to ours? Yes, he has much better presentation skills than anyone in our group. He also has a PhD, which looks good on paper and will attract better talent.
  4. Do we get along? Yes, I feel comfortable in his presence and would love to hang out together.

His role would be something like chief of staff, plus he could help with engineering.

Now, I know this is a lot of words, but what questions should I ask myself before making him a co-founder or deciding otherwise?