The freelancer is on the right track, and they should stick with their own stuff.
If money and security is the sole object, then it may more sense to take ad agency gig. But if freedom and a bigger stake in the overall direction and of company is a priority then staying the course as a freelancer may make more sense.
To me there are other factors that would come into play more than money. I imagine a Freelancer growing a business (300K) is probably spending much of their free time focused on a business and not much free time to enjoy life. There is also the instability of running a growing business which would play into it as a factor. Working for an Ad Agency might reduce those stressed, but at a 100K salary I imagine there will be other work/life balances and requests.
I don't think there is an easy answer and it all depends on the personal and professional goals of the individual. I know that's not a concrete answer, but hopefully it does help.
Keep in mind if money is what you are comparing, the financial health and opportunity at the ad agency needs to be examined closely as well. 20% of a small agency vs 20% of a large agency is very different.
You also need to consider how much control you like to have with your work, at 20%, you may not have the final say anymore. Consider whether or not your potential future partners have the same value and see if its a fit.
Ask yourself where do you want o be and what kind of future do you see yourself in? Like all good decisions, start with your objectives!
Hope this helps!
Freelancer means freedom, free from your boss and free to do what you loved to do. Don't let money take over your live, money will come by it self.
If you have a freelance practice with a circulatory valuation north or upto 300k then it's time to turn into an Agency yourself. Don't join the Agency unless your gut says you should. You should realize that you've done really well so far, something is working. Identify what that something is and nurture it. It is the secret to your continued success.
As always, however, the decision is upto none but you.
All the very best.
Impossible to say. Make a list of pros and cons. Pick the best option in balance.
Then examine your gut reaction to the choice. If you feel satisfied, then go with whatever you chose. If you feel disappointed by the outcome, go with the opposite of the rational choice.
And if you're just not sure, go on a vacation and start over tabulating the pros and cons when you have a better tan.
So many great thoughts around this ... the only thing I'd add is that a decision around solely financial principles will fail in the long term. Systems are more important than goals and Core Values alignment are more important in the long term than short or medium term promised or proposed financial gains.
Looking for Core Value alignment first empowers the freelancer to truly create synergy and leverage in the new relationship. Gaining 20% in something that has synergistic value in addition to a reasonable base may make sense if the partners are in great alignment. If not, there's no long term value to the relationship.
Tactically, the freelancer should look at the agency's systems and processes to ensure they are efficient and that there's further operational value in the alignment of their priorities.
I've written a great deal on core value alignment and you can find blogs and podcasts here: http://wisenapkin.com/tag/core-values/
Good luck and let me know if I can help.
You always have more potential when doing your own thing -- the question is whether you're able to execute.
So I'd almost always say STICK WITH YOUR OWN THING! Except we all have different goals at different points in our lives. If, for example, you want to shift your focus to family, going back to a day job might allow you to do that (in some ways) better than growing your own biz.
As someone who faced a very similar question, I need to ask first, how old are you? If you are young, energetic, and entrepreneurial (as it seems you are), it is extremely likely you will reach a point when you do not wish to be " in charge, all the time" and you will yearn for having colleagues and partners at your level, to help carry the load. As someone who was independent, then part of a large team/business, and now is independent again, I can assure you there are pros and cons to each. I would strongly suggest using a weighted factor analysis that would help you assess objectively which option is better. Its a simple excel tool, happy to show it to you. Wouldn't take more than 15 min.