Common Wealth have done a bit of work on “platform cooperatives”, you can start looking there. My start-up is structured as an employee owned cooperative. We started with a grant which got us to product market fit on a part time basis - and are now “default alive” in our current structure. I should add that we applied to and were rejected by Y Combinator after interview (narrowly a/c the rejection email). At that point I started looking around for other options. After the YC rejection I realised we were not a potential unicorn, although will in all likelihood be profitable. That realisation was incredibly helpful as it spurred me to look into ways that would not depend on fashioning ourselves as a VC casino chip. We can also build the enterprise we want to run, rather than something that appeals to a narrow (but important) class of investors.

Edit: What do you define as “successful”? We are not successful on VC metrics. But we’re happy with what we’ve built and it will make us a bit of money.