When is the right time?

So for a while I've debated when exactly would be the best time for me to have a baby. My SO wants a baby and so do i but i dont want to set us up for too much on our plate. Just as some background I am not married but my bf and I have been together for 5 years. I am going back to school for my masters in the fall. Money is tight but we strongly believe we can handle the things. However, with the exception of our plans to get married I feel like there will always be too much on our plate. Is there ever a good time to have a baby? Does anyone ever feel 100 percent ready? I want to do what's best for us so that we can build a healthy and happy family.