Well, anecdotally: After a conservatory B.M. in composition, I spent years as a freelancer, well below the poverty line, living the unglamorous life of a musician in a city. It was HARD. For that to work you have to be resourceful, optimistic, healthy overall (and not addicted to anything expensive), willing to live ultra-simply without the luxuries most of your peers are used to, and lucky (especially medically; I lived without health insurance for years, and although I carefully took care of my health, it is also damn lucky I didn't just have some accident or injury during those years).
Now I'm finally set with substantial commissions and some solid income, and I don't regret those years, but what I really want to emphasize is the temperament that got me through them. Freelancing requires you to be genuinely okay with very little income and very little stability. If you feel like you'll want more stability, don't let anyone tell you it's selling out or giving up to have a steady job (musical or otherwise). Most of the composers I most admire in my peer group do!