I'm sure there are many 'ways' to start a company and live off the net income, and there may even be an optimal way. Historically the way a lot of business owners have achieved freedom and security is 1) love what they do, so that the work isn't a chore (their work is what they would do if they could do anything in the world, which is one definition of freedom) and 2) spend/live within the constraints of the net income generated. Seems pretty simple to me since both can be chosen. This also solves the main disadvantage of you 'hav[ing] to keep running it', because you actually want to keep it running.